SERVICE
ining Cente r Printed in German y Copyright by Dr-Ing . h . c . F. Porsche Aktiengesellschaft
WKD 493 921
LIST OF CONTENTS
Test Step
Description
928 S 4
Page
Precautions for Working on Electronic Ignition Systems
0 - 02
Testing Requirements - EZK and LH
0 - 03
Conditions Caused by Faults Relay and Plug Connections on CEL
2 - 01 2 - 02
Plug Connections -- Control Unit LH
2 - 03
Plug Connections -- Control Unit EZK
2 - 04
Wiring Diagram for 928 S 4 Engine Electrical System
2 - 05
Fuel and Air Circuits
2 06
1.
Ground Points/Plug Connections - EZK and LH
2.
Power Supply for EZK Control Unit
2 -0 7 2-12
3.
Speed and Reference Mark Senders
2-14
4.
Temperature Sensor 11 - EZK
2-15
5.
Throttle Valve Switch for Idle Spped and Full Load - EZK
2-16
6.
Ignition (Ignition Timing, Ignition Pattern, Test Values)
2-17
7.
Hall Sender Signal
2 - 21
8.
Power Supply for LH Control Unit
2 - 22
9.
Power Supply for Fuel Pump I Speed Signal from EZK Control Uni t to LH Control Unit
2 - 25
10. 11 .
Air Flow Sensor Test
2 - 26
Temperature Sensor I I - LH
2 - 28
12.
Throttle Valve Switch for Idle Speed and Full Load - LH
2 - 29
13.
Fuel Injectors and Injection Timing
14.
Fuel Pressure
2 - 30 2 32
15.
Leaks in Intake System
16.
Idle Speed Control Test
2 - 34 2 - 34
17.
Resonance Flap Function Test
2 - 35
18.
Tank Vent Solenoid Valve Test
2 - 37
19.
Speed Drop in Cars with Automatic Transmission
2 - 39
20.
Oxygen Sensor Control Test in Cars with Catalytic Converter
2 - 40
21.
Generator and Regulator
2- 41
Engine Adjusting/Testing Values
2 - 44
Codes Depending on Country Equipment
2 - 45
1987
0-01
PRECAUTIONS WHEN WORKING ON ELECTRONIC IGNITION SYSTEMS
928 S 4
The requirements of modern engines on ignition systems and necessity for maintenance-free systems had led to the introduction of electronic ignition systems in standard production some time ago . Normally the ignition power of electronic systems (almost all makes) will be higher than that of conventional systems and even greater power can be seen in the near future . Consequently electronic ignition systems are corning into a power range, where even touching powers marrying parts or terminals could be very dangerous (both primary and secondary sides) .
is
in conjunction with this matter we must refer you to VDE regulations, especially VDE 01Q4/7 .61 for Germany and/or regulations/legislation of a pertinent country when repairing or testing a n ' nition system . Always turn off the ignition (switch off ignition or source of power) when working on the ignitia system_ This work would include : Connecting engine testers , .{ignition test lamps, dwell angle/speed testers, ignition oscilloscopes, etc. : ?li
Replacing parts of the ignition system (spark plugs, ignition coil, distributor, ignition leads, etc.) e mentioned dangerous voltage will be in the entire system when it is necessary to turn on theiition for ignition system tests or engine adjustments .
,.,
Consequently there is not only dangerous power in or on parts of the ignition system (for example : distributor, ignition coil, control unit, ignition tackle), but also on the wire harness (for example : tachometer connections, diagnosis plug connections), on plug connections and on testers . I
TESTING REQUIREMENTS
928 S4
Important Car Instruction s ■
Only measure resist"':e after turning off the ignition or disconnecting the battery (tester coul d be destroyed if not) .
•
Pull off both control unit plugs when testing the compression pressure (otherwise there could b e dangerous high tension, insulation damage on the ignition coil, high tension distributor an d ignition leads) .
•
Specified ignition coil (see Order Number) must never be replaced with a different ignition coil .
•
A shielded capacitor must never be connected on ignition coil terminals 1 and 15 .
•
Ignition coil terminal 1 must never be connected on ground for a burglar alarm system (ignitio n coil and control units could be destroyed) .
•
Battery positive (+) or any type of test lamp must never be connected on ignition coil terminal 1 (control unit would be destroyed) .
•
Never disconnect the ignition lead from ignition coil terminal 4 to high tension distributo r terminal 4 while operating the engine .
•
There must never be voltage flashover from ignition coil terminal 4 to ignition coil terminals 1 and 15 (control unit could be destroyed) .
s
Secondary end of the ignition must be shielded with at least 4 k-ohms to avoid destruction of th e control unit, whereby the original distributor rotor with a 1 k-ohm shielded resistor must b e installed (do not use a 5 k-ohm distributor rotor even with radio or intercom shielding) .
•
Only disconnect EZK control unit plugs with the ignition turned off .
•
Flashover or disruptive discharge in the area of the high tension distributor cap (poor insulation ) could destroy the control unit .
•
Never disconnect the battery while the engine is running .
•
Mixing up battery pole connections could destroy the control units, ignition coil or EZK contro l unit .
•
Starting the engine with outside help of more than 16 V or a fast battery charger is forbidden .
1987
0-03
TEST
928 S4
TESTING REQUIREMENTS - EZK/LH
Equi r
Working with Oscilloscop e
1 osc 1 di g 1 Bo Bo (C I 2 co t (m N ' pi e SUN Engine Tester 101 0
Bosch Engine Tester Mot 300/40 0 All sender and ignition timing signals of Porsch e models can be tested with SUN 1010/1019 / Master 3 or Bosch Mot 300/400 engine tester s recommended by Porsche . Since instructions for connecting a tester on a car vary depending on the make of tester, yo u should study the documents supplied with a tester thoroughly before making connections .
I
1 ad ; 4F twi 1 tes
Test s
Mug ' Multi
SUN Engine Tester Master 3
LH a Sender Signals Which Can Be Tested : 1 - Reference mark sende r 2 - Speed sende r 3 - ti signal s 4 - Idle speed control activatio n 5 - Hall sender signa l 6 - Ignition triggering signal to final stage s 7 - Speed pulse from EZK to LH control uni t 8 - Activating signal for resonance fla p 9 - Activating signal for tank ven t also : 10 - ti consumption signal (consumption display ) 11 - Ignition triggering signal from breakerless distributor s 12 - Reed switch signal (speedometer ) 13 - ABS wheel sensor signal s
1987
0-04
1981
TESTING REQUIREMENTS - EZKILH
928 S 4
Equipment Required for LH and EZK Tests : 1 oscilloscope (for example SUN or Bosch ) 1 digital displaying multimeter (for example Fluke 23 ) 1 Bosch L-Jetronic test lea d Bosch No . 1684 463 09 3 (Check leads for correct polarity in plugs . ) 2 control unit plug test lead s (made locally) with 2 flat male plugs , N 17 .457 .2, in order to avoid damagin g plug pins on control unit plug during tests . 1 adapter test lead, consisting of : 4 plug connectors N 017 .483 .1 wit h two approx . 150 mm long leads, soldered . 1 test lead 3-pin (for example VW VAG 1501 )
Test leads must always be used for tests !
Plug Terminal Designations : Multiple-pin plugs of control units, looking at plug terminals ! LH and EZK
353433 32 31 30 29 28 27 26 25 24 23 2221201 9 i t - r r 1817 16 151413121110 9 8 7 6 5 4 3 21
1987
0 -05
L86 1
LO - i'
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P
X
X
X
x
X
X
x
X
X
X
X
x X
X
x
X
Ground and plug connection s
X
Power supply for control uni t
X
X
w
Speed and reference mark sender s
n
o'
Throttle valve switch - idle speed
7
Throttle valve switch - full load X
X
X
x
x
x
x
X
X
x
x X
X
X
x
X
X
X
x
x
X
x
x
X
X
X
X
X
x
x
x
x
X
X
X
x
X
x
X
X
x
X
x
X
X
x
X
x
x
x
X X
PS8Z6
x
'
Hall signal
05
Power supply for LH control uni t
x
Power supply for fuel pump
X
Speed signal from EZK control uni t
x X
Ignition system + final stage s
v X
Air flow sensor Temperature sensor I I
X
Throttle valve switch - idle speed Throttle valve switch - full load
X
X
X
X
x
X
x
x
X
x
Fuel pressure
X
X
X
X
X
Leakage in intake syste m
x
X
- Activation of idle speed contro l y Activation of resonance fla p
X
X
X
oo Tank vent solenoid valve
X
x
X x
X
X
X
X
x
x X
x
w
Fuel injectors - injection timing
r 7 m a n
Oxygen sensor in cat. cony . cars Alternator 1 regulator Sflfl'd~ A8 a3Sf1V9 SNOIIIONO O
928 S
POWER SUPPLY FOR LH ! EZK CONTROL UNITS
PI
4
I r-
T
L . L
0
I1~ft'~~'1~"
a~a
IV
VI
II
V
x
VI I
1
LH-Jetronic relay XXV, which in the past only had a burn-off function, is now additionall y responsible for power supply to fuel injectors, idle speed control, tank venting valve, coding elemen t and switching valve for the resonance flap in contradiction to LH cars up to and including 198 6 models, of which the fuel injectors, oxygen sensor and idle speed control were activated by fue l pump relay XX . This was necessary, in order to permit self-diagnosis in the future .
Power Supply For : 1 - Fuel pump relay X X
Fuel pum p Oxygen senso r
2 - EZK relay XV I
LH control uni t EZK control uni t
3 - LH-Jetronic relay XX V
Burn-off functio n Fuel injector s Idle speed contro l Tank venting valve Coding elemen t Resonance flap switching valve
4-Plug W
Central electric interfac e Power supply for EZK and LH control unit s
1987
2
-02
9285 4
PLUG CONNECTIONS - LH CONTROL UNIT 2 .3
'-fData cod e Pump relay XX 85
I
Display (check )
I
CO poti (without CAT ) Family curve corr . (with CAT )
Load signal to EZK 9
Speed from EZK 1 3
(N
Throttle valve switch Idle speed Throttle valve switch Full loa d Perm . pos . term . 3 0
LC)
C'"7 (NI M■`
Electronic ground MP I X Ground from LH 2
N
Voltage from LH 3
LC) N
(0 N Tank venting valve
Jr-
+
LH-Jetronic relay XXV 8 5
Oxygen senso r
T
CO
H LM burn-of f Voltage from XXV 87
(N
C
CD Data cod e
CN
Code for oxygen family curve
fl!~
Automatic idle speed dro p
Diagnosis (K-Iead ) from diagn . conn . 1 0
t NTC I I Consumption output
AC compresso r L)
Idle speed contro l Intake pipe resonance fla p Power supply terminal 1 5 EZK relay XVI 87
1987
I I
I
I
Diagnosis (L-lead )
I n
Ground MP VII I
CD r
,, ~
Fuel injectors t i
2 - 03
PLUG CONNECTIONS - EZK CONTROL UNIT
928 S 4
wI ENG
Diagnosis (K-lead ) Temperature sensor NTC I I Knock sensor 1
Shieldin g Knock sensor 1
Knock sensor 2
Shieldin g Knock sensor 2
Hall sender 0
Speed sender +
81
Shieldin g Hall sende r Hall sender +
I
Speed sender Speed sender shield
Transmission protection switch Throttle valve switch Full load
Coding input
Diagnosis inciting lea d (L-lead ) Throttle valve switc h Idle spee d Load signal from LH 2 5 Coding inpu t
Coding input Power supply Term . 15 from XVI 8 7
.7
Speed pulse t o LH 1
88
Diagnosis plug term . 1 1 Ignition pulse to control unit 1 (left )
Diagnosis plug 4 89 1
Ignition pulse to control unit 2 (right )
90
Permanent positive 30 Ground MP IX
t 1987
2 - 04
0 Wiring Diagram Type 928S Model 8 7 ENGINE COMPARTMENT TEMPOSTAT A q
B
I.
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84
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W S - Y1'FIITE
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1987
A
G
GREEN
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9
81
82
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83
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86
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88
8S
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AND AIR CIRCUITS
TE;
928 S 4
r)
Not Tsai Mak chec Sym Alm
TES'
Engi hod ) engi r
1 - Fuel pum p 2 - Fuel filte r 3 -- Fuel pip e 4 - Distributor injection pipe s 5 - Fuel injectors A - Throttle valve housin g B -- idle speed contro l C - Ejecto r D -- Pressure dampe r E - Pressure regulato r F - Vacuum valv e G - Electric tank venting valve H --- Oil filler nec k 1 - Blow-atf valv e K - Vacuum switching valv e L - Vacuum bo x a - From fuel tan k b -- To fuel tan k c - From active carbon tan k d - From vacuum reservoi r e - To automatic transmission
Grou abov
TEST STEP : GROUND POINTS
928 S4
Note : Test steps should be carried out in the given c.rr ;e ! -io 1 is especially important ! I'llake sure that you are testing with the correct tester, with correct tester settings and on correc t .,, .~<.point in conformance with specified requirements . Symbols in Test Plan : V = voltmeter, Q = ohmmeter,= oscilloscope, < smaller (less) than , 7 = greater (more) than, °KW = crankshaft degree s read the text p recisely and without stress, in order to avoid wrong test results .
TEST STEP 1 : CHECKING GROUND AND PLUG CONNECTION S
Engine ground between engine an d body on right-hand side underneath engine .
Ground of ignition control unit s above right ignition coil .
1987
2 - 07
TEST STEP : GROUND POINTS AND PLUG CONNECTIONS
928 S 4
TES,
TEST STEP 1
TESL
Power ground underneath fuel pressur e regulator and fuel pressure damper .
Six-p cont a
Shown here on removed engine for better recognition .
Is the contact of connections good and tight?
Two-i
Plug Connection s Fuel pump (1), EZK (2) and LH (3) relays as well as plug W (4) on central electric .
.4
One each 35-pin plug on control unit s EZK (1) and LH (2) .
Plug connection for activation of ignitio n final stages (green/white lead) . Abov e central electric .
1987
2 -08
B 54
TESTSTEPf PLUG CONNECTIONS
928 S 4
TEST.STEP 1 Six-pin plug on air flow sensor (only 5 plu g contacts are used in the plug receptacle) .
17
iition. Two-pin plug on temperature sensor I I .
Three-pin plug on speedlreference Sender .
nark
Two-pin plug on each of eight fuel injectors (first remove cover for ring pipes) .
- 48
1987
2-.D9
TEST STEP 1 Plug connections of knock sensors . Front sensor -- plug connection underneath fUel ring pipe at left front .
--~
j
Plug for t cove neat
4
S..
Rear sensor - plug connection above fuel ring pipe at right rear .
Hall sender plug connection, Behind housin g
for camshaft drive gear - cylinder ban k 1 -4 .
D i sr Sin t on e as l and or Mal
Plug connection of solenoid valve for resonance flap operation (at toothed belt cover , cylinder bank 5 - 8) .
this
mu
2 -D
1ST
TEST STEP : PLUG CONNECTIONS
928 S 4
TEST STEP 1 Plug connection of solenoid valve for tank venting (at toothed bel t cover, cylinder bank 1 - 4, underneath water hose) .
Plug connections of final stage s (on hood lock cross wall at left hand side) .
121 7
Are these plugs connected correctly, not loose and not corroded ? Disconnect plugs ; plugs must not be bent on the pin or receptacle ends and also not corroded ! Since 928 S 4 cars are only fitted wit h one standard control unit (EZK as wel l as LH) worldwide since 1987 model s and these control units are coded t o pertinent country equipment requirements (see page 2 - 47 of Test Plan) , this code must be checked in case o f complaint . Coding element is located on back o f the control unit carrier . Control unit s must
1987
be removed for checking .
2-11
928 S 4
'ST VALUES - EZK
Ti- S
TEST STEP 2 : POWER SUPPLY FOR EZK CONTROL UNIT (V )
wer is supplied to EZK and LH control units of 928 S 4 cars via ignition lock terminal 15 as well a s additionally from battery + (permanent positive terminal 30) since 1987 model s
Permanent Positiv e Connect voltmeter on terminal 18 e Ici terminal 35 q f control unit plug . Display' bartte y voltage . 25
J .,itmeter on W 22 of connected CEL plo y ?hody) . tt ry voltage .
1r 23
Display : dge U 12 and W 22 on CEL plug with a test lead . ~nneet voltmeter on terminals 18 and 35 of contro l unit pl u 'splay : battery voitaw .
Im p
If the control unit plug has voltage in this test, th e . r -dition is located within Central Electrics . if the control unit plug does not have voltage, chec k .,.ring ' to CEL. plug U 12 according to the Wirin g Diagram . .
353433 3231 3029 28 27 26 25 24 23 2221201 9
11 ~ti 18 1716 15 14 13 12 11109
1987
Central Electric Plug W
8
7
a . -
-J
6 54 3 2 1
r
1!
TEST VALUES - EZK
928 S 4
b) Power Supply via EZK Relay (XVI ) Connect voltmeter on terminal 18 and terminal 29 of disconnected EZK control unit plug . Turn on ignition . Display : battery voltage . No Display : Connect voltmeter on W 14 of CEL plug and ground (body) . Turn on ignition . Display : battery voltage . If battery voltage is displayed, check power flow from CEL plug W 14 to terminal 29 o n EZK control unit plug . if there is no display, remove EZK relay (XVI) and bridge terminal 87 and 30 on relay socket . Now connect voltmeter on terminals 18 and 29 of control unit plug (however, ignitio n remains off for this test) . Display : battery voltage . If battery voltage is displayed, check EZK relay and/or activation , No Display : Check voltage and ground supply on EZK relay socket to wiring diagram . Important : Burglar alarm control unit or a plug bridge must be connected between B 23 an d F 25 of the CEL plug .
35 34 33 32 31
.si
79 28 27 26 25 24 2322 2120 1 9
%la17 16 15M13 12 I110
1987
9 8 7 6 5 4
3 21
2 - 13
TEST STEP 3 : SPEED AND REFERENCE MARK SENDERS
(1
1)
.,
test step can only be carried out with an os t Connect and adjust a workshop oscilloscope to insr< (set display screen range to 20 V for Bosch MOT 3OL ..4 ;1 .
: urpplied with the tester for this purpos e sl . E
Connect positive test lead via auxiliary lead on control unit terminE ;i 23 and negative tester lead vi a auxilia r y lead on control unit terminal 6 (terminal 24 via auxiliary lead on ground") .
Crank engine with the star 1 :r motor . Sine oscillation of at least 3 V (speeA l.: 'haher amplitude (reference mark) must be seen on the scr,Tr?
Spee d signa l 7 c+7 A
2 - Referenc e mark signa l
i A
Sender distance cannot be adjusted . If there is insufficient or no deflection {C 3 V speed pulse ) displayed on the screen, check connections or measure lead connections ; replace sender . * Note :
If there is a signal with tester connections an terminals 23 and 6 of the EZK contro l unit and terminal 24 is connected with ground during the test, the signal most h e Slhle in the same form, If not, there is a short circuit in the sensor lea d
TEST STEP 4 : TEMPERATURE SENSOR II I EZK SID E ENGINE TEMPERATURE (Q )
Pull off EZK control unit plug .
Connect ohmmeter on terminal 19 and terminal 18 of EZK control unit plug; Test values at
C = 4 .4- 6 .8k S 15--30°C= 1 .4- 3 .6k 4 1 - 1 .3k Q 40°C= 80°C250-390 5 100° C = 160 - 210 Q
not reached, check sensor itself . In so doing don't connect ohmmeter o n both contact lugs, but instead check eac h plug contact on temperature sensor agains t ground (two independent temperatur e sensors) . If
,e
1 --- EZK sid e 2 - L H sid e Note : Temperature sensor 11 advances the ignition timing of a cold engine for better engin e pickup .
1987
2-15
TES
928 5
e) Ad
TEST STEP 5 : THROTTLE VALVE SV1ETCH (C?
Three Loos speed Idle s Full I
a) Idle Speed Contac t all off LH control unit plug . innect ohmmeter on to , final help of auxiliary lea n
.find
i EZ~ :r .
termir,
unit plug wi s
Note: With throttle valve closed ith throttle valve opened
display : < 10 Q display : 00 Q
idle speed contact must open (break) immediately (< 1 0 throttle valve 4 ) ate : A breaking idle speed contact placer (advanced approx . 10 0 Break .
th
riition •,
in partial I
.- .L .rrv e
TEST Cents
Mlle speed ignition timing approx . 20 0 - r anksha f coasting shutoff, higher idle s r cult :
. :sting shutoff while racing engine, one time •: :' i tion timing retarded approx . 1 0 n
At idl At co
ch engine start .
EZ K the "+ cann t It l
b) Full Loa d ,nnect ohmmeter on terminal 26 ar -Id ten rii :im„ id O f dicortnected EZK control unit plug wit h of auxiliary leads . LH control unit plug must also be disconnecte d
;help
ith throttle valve closed ;er approx . 213 throttle valve travel Note :
A closing (making) full load contact retards the ignition timing into the full load famil y curve l } timing advanced appiux . 15 lull load enrichment .
Brie
ii 1
25`' in f u
Circuit : Ignition timing retarded apfrc,x . 15 -- 25 0 in partial loan rang e
Check whether throttle valve moves ?c
19B7
Ifs * the 1g Firir>n
display : display : < 10 Q
:out entire ieretinci
-16
c) Adjusting Throttle Valve Switc h Throttle valve in idle speed position . Loosen screws of throttle valve switch and turn throttle valve switch far enough, until the idl e speed contact switches . Idle speed contact must switch while opening the throttle valve after a gap of approx . 1 0 . Full load contact is adjusted automatically with the idle speed contac t Note : Intake branch must be disassembled to adjust a throttle valve switch .
TEST STEP 6 : IGNITION
S\.c_
14 1 V )
Controlling Ignition Timin g At idle speed of 675 ±25 rpm At control value of 3000 rpm
10 ± 2° before TD C 32 ±4 0 before TD C
EZK control unit does not have a vacuum connection (load sensor), but instead now receive s the "engine load" information as an electronic signal from the LH control unit . This signa l cannot be checked with common workshop equipment . If this load signal is missing on an EZK control unit, ignition timing will be retarded up to 25 0 on crankshaft in partial and full load ranges (full load family curve, as protective circuit) ! if a secondary display appears on the oscilloscope, engine tester must be set to 4 cylinders sinc r the ignition system is divided into two separate ignition circuits . Firing order : 1--3-7-2-6-5-4-8 . ignition Circuit I : High tension distributor on exhaust camshaft, cylinders 1 - 4 : 1-7-6---4 ignition Circuit II : High tension distributor on exhaust camshaft, cylinders 5 - 8 : 5--8--3- 2
1987
17
928 S 4
An ignition coil installed at right front as seen looking forward in car is responsible for high tensio n wer supply of ignition circuit 1, while the ignition coil installed at left front is responsible for hi- L orin pnwr'- :apply of ignition circuit ll . PrI n Sec ( Vo l
a) Connection of Engine Test :: : Connect engine tester to instructions supplied with tester and adjust (note 4 cylinder test range) . It ignition ;.,_;rtern of ignition circuit I (right-hand side) is visible, connect tester on cylinde r ignition le, 2nd right front ignition coil
Hig l Dis t V ist Js s V Spa ' Shi E :~is~
7
Cylin
6
ignition pattern of ignition circuit I I (left-hand side) is visible, connect tester on cylinder 5 .gnition lend, :,nri [eft front ignition coil . If
o Cylinders .
5
8
3
2
5
Note : If a fault is displayed for all cylinders, it is in the primary or secondary circuit betw e the ignition coil and distributor rotor . a fault is displayed for only one cylinder, it is after the distributor roto r
1937
TEST VALUES - EZK
928 S 4
b) Resistance on Ignition Coil, High Tension Distributor and Spark Plug Connector s Ignition Coil (S2 1 V) : Primary resistance Terminals 1 + 15 Secondary resistance Terminals 1 + 4 Voltage on terminal 15 with engine running
0 .4 - 0 .7 C ? 5 .0 - 8 .7 k g > 10 V
High Tension Distributor (C ) : Distributor finger shielded resistance Visual inspection for damage and traces of burnin g as well as cracks in cover . Spark Plug Connectors (52) : Shielded resistance Visual inspection for damage, traces of burning an d oxidation .
1 kg
3 kg
c) Activation of High Tension Sid e ignition triggering signal can be simulated for fast ignition end troubleshooting . This is accomplished by disconnecting a two-pin plug (arrow) above CEL (green/white lead) . Connect plug pins with an auxiliary lead . Connect oscilloscope tester lead terminal 4 on ignition lead terminal 4 .
1887
2-19
TEST VALUES - EZK
928 S 4
Turn on ignition . Now if positive is applied on one of both plug pins in intervals with help of tie auxiliary lead, a high tension needle (ignition triggering) must appear on the oscilloscope each time. If no signals appear, check power supply of final stage and ignition coil , ground point for final stages (underneath right ignition coil) , - plug connections on final stages, ignition coils and high tension distributor , -- components (e .g . ignition coils, ignition leads, spark plug connectors, etc .) responsible for high tension an d -- power flow in leads from control unit plug to final stage (green lead for ignition circuit I an d white lead for ignition circuit I1) .
,d
g't ontrol Signal for Final Stage
(I)
Carry Out test on both disconnected fina l
plugs . , Connect positive tester lead on terminal 5 and negative tester lead on terminal 2 of disconnected final stage plug . Operate starter motor . Oscilloscope should display a contro l Sjgnal on each final stage plug .
1987
2 -20
TE 5
TEST VALUES -- EZK
928 S 4
Important Note : Baseplate must be coated with a heat conducting paste prior to installation o f final stages . Never apply heat conducting paste on painted parts . Heat conducting paste : Bosch No . 5 942 860 003 .
- Final stag e Baseplat e
TEST STEP 7 : HALL SENDER SIGNAL (+
)
V Vie' - 15 0 1
Disconnect plug on cylinder head 1 - 4 behind camshaft drive gear and connec t a 3-pin adapter lead IVW 1501) betwee n plug and cylinder head to test the hal l signal . Connect positive and negative tester lead s on terminals 1 and 2 of adapter lead, connect tester to instructions supplied wit h tester and start engine . Following signal will appear on screen, i f hall sender system is okay . If hall signal or one of knock sensor signals is missing, ignition timing will be re . tarded by about 6 0 for all cylinders i n upper partial load and full load range s by the control unit (protective circuit),
Voltage signal approx . 5 V
1987
2 . 21
TEST
.!ES - LH-JE';- ; :. . :
SST STEP 8
E-,
92 8
. SUPPLY FOR LH CONTROL UNIT (V ) P
an (
a) Permanent Positiv e "Connect voltmeter on terminal 17 Display : battery voltage .
and terminal 4 of LH control unit plug with help of auxiliary lead .
liNo Display : Connect voltmeter on CEL plug W 22 and ground with help of auxiliary 'Display : battery voltage .
lean.
If battery voltage is displayed, check power flow in lead from CEL plug W 22 to control unit plu g terminal 4 , No Display : ,C_onnect U 12 and W 22 of CEL plug with help of auxiliary lead . Connect voltmeter on terminal 1 7 And terminal 4 of LH control unit plug with help of auxiliary lead . Display : battery voltage . !Battery voltage displayed = condition within CEL . No display = check power supply to wiring diagram .
35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 1 9 ----------------- 18 17 16 15 14 13 12 11 10 9 8 7 5 4 3 21
t
A
1987
4
2 - 22
i 28S4
y lead,
TEST VALUES - LH-JETRONICC
b) Power Supply Via LH Relay XX V Connect voltmeter on terminal 17 and terminal 9 of LH control unit plug with help of auxiliary lea d and apply on ground terminal 21 (body) with help of auxiliary lead . LH relay must be activated . Display : battery voltage . No Display : Connect voltmeter between connected CEL plug W 23 and ground and then connect between termina l 17 and terminal 21 of LH control unit plug with help of auxiliary lead (ground signal to LH relay) . Display : battery voltage . If battery voltage is displayed, check lead connection between CE L plug W 23 and LH control uni t plug terminal 9 . No Display : Remove LH relay (XXV) and bridge terminals 87 and 30 on relay socket . Connect with voltmeter o r LH control unit plug terminals 17 and 9 with help of auxiliary lead . Display : battery voltage . Battery voltage displayed = check LH relay and its activation . No voltage displayed = check lead connections to wiring diagram .
,I
353433 323130 29 28 37 26 25 2423 2221 201 9
----------------- 18 17 16
1987
15
14
13 12
1110 9 8 7 6 5 4 3 2 1
J
2 - 23
~
.
~
.
TEST VALUES
LH-JETRONIC
9288 4
mjPower Supply VimFZK Relay XV I Connect voltmeter on terminal 5 and terminal 35 of LHomntno! unit plug . Turn on ign!tk*n.Dimolay : battery voltage . No Display : Connect voltmeter on connected CE Lplug VV 14 and ground . Ignition on . Display : battery voltage . If battery voltage is displayed, check lead connection between CEL p!uQVV 14 and LH contnnl uni t plug terminal 35 .
No Display : Remove EZK relay and bridge terminal 87 and terminal 30 on relay socket . Connect voltmeter o n terminal 35 and ternn(na! 5 of LH control unit plug . Display : battery voltage . Battery voltage displayed = check EZK relay and its activation . No voltage displayed - check lead connect ions to wiring diagram .
~~ ~
35 34 33 32 31 30 19 28 27 26 25 24 23 2221 20 1 9 - 18
17
16 15
14 13 12 11 109 8 7 6 5 43 2
+
°+
~
~^
.~
. .,
-
~
.`
'
"
, .
..
_=
^
-
,
1987
2 '2 4
-
TEI
',`+LUES - LH-JE
! .iNIC
9 28 S 4
STEP 9 : POWER SUPPLY FOR FUEL PUMP (V ) Fuel pump ieiay XX is activated with ground from LH control unit . Check ac,avation of fuel pump by bridging terminal 20 and terminal 17 on LH control unit plug wit h help of an auxiliary lead . Turn on ignition . Fuel pump runs . Does Not Run : k fuse no . 42 . If fuse is okay, remove fuel pump relay and bridge terminal 87 and terminal 30 o n d•i socket . Fuel pump must run .
.,r n ;)
if pump runs, check relay and its activation . If pump does not run, check leads and connections for fuel pump and/or fuel pump itself .
■
rib
353433 323130 29 28 27 26 252423 2221201 9
18
l
: :---- : : :- - - -1 -17 16 15 14 1312IT 109B7 6 5 4 3 21
ri
Speed Signal from EZK Control Unit to LH Control Unit fl ) Important :
EZK control unit plug connected, LH control unit plug disconnected .
Connect terminal 17 and terminal 1 of LH control unit plug with engine tester leads with help o f auxiliary leads . Set oscilloscope to instructions supplied wit h tester, start engine with starter motor . Control signal must appear on oscilloscope .
2-2 5
TEST VALUES -- LH-JETRONIC
928 S 4
If no signal appears, check power flow from LH control unit plug terminal 1 to EZK :MUM Uni t plug terminal 13 . If there is power flow, replace EZK control unit .
35 34 33 32 3130 29 28 27 26 25 2423 2221201 9
1817 16 15 1413 121110 9 8 7 6 5 4 3 21
TEST STEP 10 : LH AIR FLOW SENSOR (Vlsrl) :a) Power Supply
(V)
Pull off plug on air flow sensor. Connect voltmeter on plug terminals 2 and 4 with help o f auxiliary leads .
Connect terminal 17 and terminal 21 of disconnected LH control unit plug with help of auxiliar y lead . Display : battery voltage . No Display : Remove LH relay XXV and bridge terminal 87 and terminal 30 on relay socket . Display o f voltmeter connected on air flow sensor plug : battery voltage . Battery voltage displayed = check LH relay and its activation . No voltage displayed = check lead and plug connections to wiring diagram .
11 8 S 4
TEST VALUES - LH-JETRCNIC
928 S 4
6) Resistance Test of Hot Wire Circuit on Air Flow Sensor (Q ) Disconnect plug on air flow sensor_ Connect ohmmeter on terminals 3 and 5 of air flow sensor . Display : 3 .6 - 4 .1 0
c) {decking Hot Wire Signal (V ) Connect plug on air flow sensor . Remove LH relay XXV and bridge terminal 87 and terminal 3 0 on relay socket . Connect voltmeter on terminal 6 and terminal 7 of LH control unit plug . Display : = 1 .6 V Blow air on hot wire in air flow sensor and observe the voltmeter . There should be a change in voltage (-1 .6 -5 VI .
35 34 33 32 3130 29 26 27 26 25 24 23 22 21 20 1 9
18 171b 15 14 1312 11 10 9 S 7a5 4 3 21
+ + d) Checking Burn-off of Hot Wire Circuit (Visual Check ) Run engine with installed and connected air flow sensor . increase engine speed to more than 2000 rpm after engine has reached a temperature of 7 60 0 C and then stop the engine (ignition off) . Hot wire must glow (burn-off function) approx . 1 secon d after waiting approximately 4 seconds .
e) Emergency Running Program ( s )
An emergency running program is stored in a memory of the LH control unit and is activated, i f the air flow sensor fails . The car can then be driven to the nearest authorized workshop . Warm engine and speed < 2000 rpm - 3 .5 ms t i Warm engine and speed > 2000 rprn - 6 .3 ms ti
1987
(ti = injection time )
2 . 27
TEST VALUES- .LH~I
tR 11i.IC
928 S 4
TEST STEP 11 : TEMPERATURE SENSOR I I - LH
.
Disconnect LH control unit plug . Connect ohmmeter on terminal 13 and terminal 5 or 17 of LH control unit plug with help o f auxiliary leads.
353433 32 3i3029 28 27 2!► 25 24 23 22 21 20 1 9
18 177615
4
14 13 12 11 10 9
+
8 7 6 5 4 3 21
+
Display: Resistance Test value at 15-
0° C = 4 .4 - 6 .8 k g 30°C= 1 .4- 3 .6k Q 40°C= 1 .0-- 1 .3 k0 800 C=250-290 0 1000 C = 100-210 0
If values are not reached, test direct on sensor . in so doing do not connect ohmmeter on bot h contact lugs, but instead check each contact lug against ground separately (two independent temperature sensors) .
Note : Temperature sensor I I sends information on engine temperature to the control unit . It causes an enrichment of the fuel/air mixture for cold starts and warming up .
TEST VALUES - LH-JETRONIC
Break
S2) :
928 S4
Excessively rich mixture . Engine in warm state stalls and cannot be started again . Emergency running can be reached with bridging (0 Qi in case of a brea k 0)
Short Circuit (0 0f :
No engine pick-up in cold state, mixture too lean, stalls . No effect at operating temperature .
TEST STEP 12 : THROTTLE VALVE SWITCH (Q ) o) Idle Speed Contac t Disconnect plug on EZK control unit . Connect ohmmeter on terminal 17 and terminal 2 of LH control unit plug with auxiliary leads . < 10 Q Display : throttle valve closed o0 4 throttle valve opened> I° Idle speed contact activates coasting shutoff . = no coasting shutof f Break Short circuit = coasting shutoff one time while racing engine after each engine start .
35 34 33 32 31 30 29 28 27 26 23 24 23 23 21 20 1 4
L
1817 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
"
TEST VALUES - LH-JETRONIC
928 S 4
II
b) Full Load Contac t Connect ohmmeter on terminal 17 and terminal 3 of control unit plug with auxiliary leads . Als o disconnect plug on EZK control unit . Q Display : Throttle valve closed Throttle valve opened approx . 2/3 of distance < 10 Q Full load contact activates full load enrichment . Break = too lean with full load, power output insufficient . Short circuit = enrichment too early, high fuel consumption . I
f
35 34 33 32 3130 24 28 27 26 25 24 23 2221 20 1 9 18 17 16 15 14 1312 11109
7 6 5 4 3 2 1r 1
See Test Step 5 c for switch adjusting procedures .
TEST STEP 13 : FUEL INJECTORS - INJECTION TIMING (V/Q/
)
a) Fuel Injector s If it is possible to run the engine, pull off injector plugs seperately . Engine speed will drop in case o f good fuel injectors or perfect combustion . Proceed as described below when engine cannot be run . Pull off injector plugs (after first removing cover on the ring pipe) . Remove LH relay XXV and bridg e terminal 87 and terminal 30 on relay socket . Connect voltmeter on injector plug contacts and groun d with help of auxiliary leads . Display : battery voltage . Check leads and connections to wiring diagram, if there is no display . Check coil resistance on connecting contacts of fuel injectors with an ohmmeter . Test value :- 16 S?
928 S 4
TEST VALUES - LH-JETRONIC
928 S 4
b) injection Final Stage Adjust oscilloscope to instructions supplied with tester . Connect Bosch test lead (1 684 463 093) between on fuel injecto r and plug . Connect tester leads on test lead s to instructions supplied with tester .
Cautionl Tester leads must not hav e contact with ground .
; ;icrt engine . Following pictures must be displayed when injection final stage is working correctl y and test connections have been made correctly .
Note :
Starter speed
If engine does not star t or idle speed drops ,
tjrot-
change tester connection s on test leads and chec k tester adjustments .
Idle speed
ti re 1987
2-31
TEST VALUES - LH-JETRONIC
92854
Accelerating
Decelerating
If "ti" is not stoppe d while decelerating, se e Test Step 12 a l
TEST STEP 14 : FUEL PRESSURE. A test connection is located on the fue l ring pipe at right front . Unscrew capped nut on test connection .
I portant :
1987
Inserted sealing ball coul d fall out . Connect pressure teste r P 378 on adapter .
2-32
928
JETRONIC
928 S 4
Start engine, at idle speed with vacuum on pressure regulator : Test pressure : 3 .3 ± 0 .2 bar . Test on stopped engine and running fuel pump without vacuum on pressure regulator (for thi s purpose fuel pump relay XX is removed and terminals 87 and 30 bridged) : Test pressure : 3 .8 ± 0 .2 bar . Slowly pinch return hose of pressure regulator with a hose clamp (e .g . at fuel level transmitter) : Fuel pressure with running pump less than 4 .5 bar = check fuel filter, replace fuel pump . Hot Starting Problem s Fuel pressure of a warm engine may drop by maximum 0 .5 bar in 30 minutes (pressure holdin g test) . Causes for Hot Starting Problem s
Parts :
Test :
Pressure regulator leakin g
Pinching return hose
Electric fuel pump check valve fault y
Pinching pressure hose
Fuel injectors leakin g
Pinching both hoses
Radiator fan running on
See pages 9 - 09 and 9 - 10 in 198 7 Model Info-m :ition ff,! f
19 ;
r
2
TEST VALUES - LH-JETRONIC
92854
TEST
TES's
Peck tightness of all connec lions after air flow sensor an d for leaks . Mount locally made too o n air flow sensor with 4 x 45 screws and build up 0 .3 ba r pressure. Pressure will drop in. intake system or escaping ai r will be heard in case of leaks .
re w
0>3 11
TEST STEP 16 : ACTIVATION OF IDLE SPEED CONTRO L Bridge terry anal l 7 and terminal 21 on control unit plug with help of auxiliary lead . Apply groun d (n terminal 33 of control unit plug in intervals with help of auxiliary lead . Fuming of idle speed control will be heard up to the stop .
T
T
35 34 33 32 31 30 24 28 27 76 25 24 23 22 21 20 1 9
18
4
17
16 15 14 13 12
fl 109
8
76 5 4 3 2 1
- ----------------
r
ks .
is
TEST VALUES - LH-JETRONI C
92BS 4
TEST STEP 17 : ACTIVATION AND FUNCTION OF RESONANCE FLA P A resonance valve in the intake system will be opened by vacuum in certain speed ranges and wit h east 1/3rd engine load . This is also applicable to each start (requirement : vacuum in suppl y k) . a) Checking Flap Functio n Remove cover (rubber cap) of the resonance valve shaft above the intak e Web . q raw a center line on the surfac e of the valve shaft with a soft-tip pen o r something similar (makes it easier U1 recognize opening movement) . Start engine : valve opens and closes during starting procedures . Accelerate abruptly to wide ope n
throttle after engine is running : valv e opens and closes , (Conditions : speed greater than 3500 rpm and at least 1/3rd engine load )
b) Checking Resonance Flap Functio n without Running Engine : Vacuum En d Pull off vacuum feed hose from suppl y tank on solenoid valve . Check vacuu m with a vacuum tester : -0 .6 bar
A - From vacuum tan k B - To resonance fla p
1987
2 - 35
3 TES1
Now supply approx . 0 .4 bar vacuum in the hose leading to the diaphragm valve (below intake web ) with a vacuum pump = resonance flap opens . Flap Does Not Ope r diaphragm valve
( layout drawing (page 2 - 06) .
c) Power Supply (V I Bridge terminal 17 aria terminal 21 on LH Control ground on terminal 34 of control unit plug with ano[', ,
nelp of an auxiliary lead . Appl y •uxil i y lead = resonance flap open s
Flap Does Not Open : Connect terminal 17 and terminal 21 on LH control unit plug . Disconnect Connect voltmeter on plug recept-3w 1 ?1 and ground . Display : battery voltage . No Display : Check power supply T : , valve via LH relay XXV t- n wrin g auram and test power i low fro m i'rnilrol unit r, a al 34 t o _ction
1
plus :
in
solenoid va i
2
(l) Checking Control Signal with Oscilloscope (E . Connect LH control unit plug . Disconnect plug an solenoid valve- Connect engine tester o n receptacle end of solenoid valve plug to instructions supplied with tester with help of auxiliar y leads and adjust the tester (with Bosch MOT 300/400, however select screen test range 20 V) . Following picture must be displayed on tester while starting engine as well as with running engine` and abrupt opening of the throttle valve .
TEST VALUES -- LH,JETRONIC
928 S 4
TEST STEP 18 : SOLENOID VALVE FOR TANK VEN T LH control unit activates and opens the solenoid valve with a timed ground signal when engine ha s operating temperature and the throttle valve (idle speed contact) is open . Opening time of solenoi d valve is longer as the air flow rate in the air flow sensor increases .
i I a) Checking Activatio n Connect terminal 17 and terminal 21 on LH control unit plug with auxiliary leads . Apply ground (body) to terminal 27 with an additional lead : solenoid valve opens . Valve Does Not Open : Check power supply and power flow from LH control unit terminal 27 to solenoid valve to th e wiring diagram .
r
b) Checking Power Supply IV ) Connect terminal 17 and terminal 21 on control unit plug with auxiliary leads . Connect voltmete r on plug connector and ground of disconnected solenoid valve plug with auxiliary leads . Display : battery voltage . No Display : Check power supply via LH relay to wiring diagram .
I
353433 323138 29 28 27 26 25 2423 2221 20 1 9 ------------------------6151413 12 11109 8 76 5 4 3 21
~18 17
r
928 S 4
TEST VALUES - LH-JETRONIC
c) Checking Control Signal with Oscillos
'(
Connect q ME test lead (Bosch No . 1 684 463 093) between solenoi d valve and plug connection . Connect and adjust engine tester to instructions supplied with tester (with Bosch MOT 300/400, however select screen test range 20 V) . Start engine and accelerate lightl y `idle speed contact must open, engine temperature > 60 0 C)-, Following picture is displayed.;
Signal is wider as air flow rate increases!
Tank ven t
1987
2 -38
TEST VALUES -- LH-JETAONIC
928 S4
TEST STEP 19 : CHECKING ACTIVATION OF SPEED DROP FOR ENGAGING DRIVE RANG E I .N CARS WITH AUTOMATIC TRANSMISSION (Q)
a) Connect ohmmeter between terminal 17 and terminal 30 of disconnected LH control unit plug wit h help of auxiliary leads .
.
t
353433 373130 29 28 27 26 25 24 23 22 21201 9 : 18 17 16 1514 13 12 11 109 876 5 4 3 21
4 Selector lever in P or N : Selector lever in R or q or 3 or 2 :
Display : < 10 0 Display :cc 0
If these display values are not reached, check wiring via plug V 14 and U 23 to starter switch o n transmission to the wiring diagram .
IA Checking with Engine Runnin g Connect control unit plug, Start engine and operate brake pedal . Selector lever in R or D . Idle speed must now drop by approximately 30 to 50 rpm . Caution : danger of accident because of rolling car!
TEST VALUES - LH-JETRONIG
928 S 4
TEST STEP 20: CHECKING OXYGEN SENSOR IN CARS WITH CATALYTIC CONVERTER (V) Simple checking of control can be carried out in spite of adaptive oxygen sensor control .
a) Checking Sensor Signal (V) Disconnect oxygen sensor plu g close to central electric . Connect voltmeter with each plug pin on sensor end and ground .
Test connectio n Display on voltmeter : 0 .1 - 1 .0 V Start and run engine warm, so that oxygen sensor reaches its operating temperature . An voltage signal must be displayed when enrichening the (e .g . by acce!erat+nc ; vacuum hose on fuel pressure regula r
Increas e
b) Checking Control Uni t Run engine to operating temperature . Connect emission tester on exhaust test pipe in engine compartment . Supply ground to plug receptacle on control unit end of disconnected oxygen sensor plu g with help of auxiliary lead and observe the emission tester .
Ground CO level must rise . Caution : Only perform this test so long, until a change in CO level is recognized on the CO tester . If a control unit does not process the ground signal, check its code (see page 2 - 47 in Test Plan ) before replacing the control unit .
1987
40
•f
I
TEST VALUES - LH-JETRONIC
TEST STEP 21 : ALTERNATOR / REGULATO R Peak voltage of alternator could cause misfiring . Take off drive belt on alternator, start engine check alternator and regulato r if this eliminates the problem .
928 S 4
TEST VALUES
928 5 4
LH-JETRONIC
INFORMATION FOR CHECKING IDLE SPEED AND IDLE SPEED C O
a) Idle Speed The engine of 928 S 4 cars has adaptive idle speed volumetric efficiency control since 1987 models . This means the omission of idle speed adjustments for all versions . Idle speed can now only be checked . On a warm engine it is : 675 ± 25 rpm . b) Idle Speed CO for Cars without Cat . Cony . CO adjustments on air flow sensor of 928 S 4 engines are no longer possible . A potentiometer , with which the CO level can be changed, i s mounted on the holder of control units fo r this purpose . Following requirements must be fulfilled fo r CO level adjustments . - Engine at operating temperature -- Air injection disconnecte d --- All electric equipment switched of f - Engine and ignition in perfect conditio n - CO tester at operating temperature, cali brated and adjusted Adjustment : 0 .5 - 1 .5 % C O at 675 ± 25 rpm and ignition timin g 10 ± 2 0 before TDC . Make sure that adapter plug 91 1 .612 .422 .0 0 is connected on oxygen sensor connecting lea d of cars without catalytic converters, in orde r to avoid dispersion (see wiring diagram) .
A - TDC sende r B - CO test pipe s
1957
2 -42
TEST VALUES - LH,IETRONIC
9285 4
c) Idle Speed CO for Cars with Catalytic Converte r In these cars there is adaption of the idle speed CO level in addition to adaption of the idle speed , so that only the actual condition can be checked on such cars . The potentiometer is also omitte d on the holder of control units because of this . Following requirements must be fulfilled for CO level checking . - Engine at operating temperature - Oxygen sensor plug connected - All electric equipment switched of f - Engine and ignition in perfect conditio n -- CO tester at operating temperature, calibrated and adjuste d Test value : q .4 - 1 .2 % C O at 675 ± 25 rpm and ignition timing 10 ± 2° before TIC . After disconnection of control unit plugs or disconnecting the battery the engine must be ru n at idle speed afterwards at least 10 minutes, before a test of these values can be carried out again .
S
S
;M
1987
2-43
IDLE SPEED HC VALUES FOR PORSCHE CARS
9285 4
A Values Applicable Worldwide :
75 Model,
76 Model
'77 Model
78 Model
79 Model
'80/'81 Mod .
'821'83 Mod .
911 1300 ppm )
911 (300 ppm l
911 (300 ppm)
911 SC (300 ppm)
911 SC (260 ppm)
911 SC (260 ppm)
911 S C 300 pp m
911 S (300 ppm)
Carrer a 1500 ppm)
Carrer a (300 ppm)
930 Turbo (300 ppm)
911 Turb o 1250 ppm)
911 Turb o ppmY
911 Turbo C 300 pp m
Carrera 1500 ppm)
930 Turbo (300 ppm)
930 Turbo (300 ppm)
924 (400 ppm )
924 (280 ppm)
1 924 (280 ppm)
92 4 300 ppm
(250
84-87 Mod .
aa
a o o in
1
930 Turbo (300 ppm)
924 (400 ppm)
924 (400 ppm)
928 (300 ppm)
924 Turbo 4340 ppm)
924 Turbo (340 ppm)
924 Turbo 340 ppm
928 (290 pp m)
928 (310 ppm)
928 C 300 ppm
928 S (310 ppm)
928 S 300 ppm
VfV1 C
0U
u u
0 . m T
u
M .C03 .C
Q3 3
944 4 300 pp m
Please apply these figures with the following limitations . 1.
Idle speed CO, ignition timing and idle speed must be adjusted to specifications .
2.
As for all idle speed CO tests secondary air injection must be disconnected if applicable to car .
3.
There is surely a fault in the mixture control unit/injection pump, spark plug or fuel injector , if specified HC values are exceeded . On the other hand there could even be a fault when H C values are too low . Consequently engine running at idle speed, etc ., must still be used as criteria for evaluatiop.
198 7
2 - 44
E
CONTROL UNITS -- CODES
928 S 4
Wiring Diagram
e
Version
06040 2
~705
03 0 ~
•, • \i~ •C- •7 i
a3
1
ECE,
Porsche Numbe r
Manual Transrn .
928 .607 .431 .00
without catalytic converter ECE,
Autom, Transm .
928 .607 .432 .00
without catalytic converter Worldwide,
Manual Transm .
928 .607 .433,00
with catalytic converter r, t
.~
Worldwide,
Autom . Transm -
928 .607 .434.00
with catalytic convener
Ob
®l -
z•:
05
O :~ 0 o
080F • ,1 o
0
Australia, Manual Transmission
928 .607 .435 .00
Australia, Automatic Transm .
928 .607 .436,00 l
