Porsche 1989 944 S2, Workshop Manual

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944 S/944 S2 Fuel System - Electronic Control
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Plug Connections
Are all plugs connected correctly, not loose
and not corroded?
Disconnect plugs and check whether pins
and terminals of plugs are bent or corroded.
55-pin plug an DME control unit (behind
floor plate in the front passenger's
footwell).
14-pin plug in engine compartment next
to the brake booster.
3-pin plug for reference mark/speed
sender and 3-pin plug for oxygen sensor
behind the intake pipe for cylinder no. 4
(first remove cover an the fuel ring-pipe).
3-pin plug an throttle valve switch.
2-pin plug on electromagnetic valve for
tank venting (an brake boaster).
4-pin plug an air flow sensor.
2-pin plug an NTC II (temperature sensor
is screwed in the engine block above the
left compensating shaft near cylinder no.
1).
7-pin plug on ignition final stage in the
engine compartment at front left.
3-pin Hall sender plug (behind the
camshaft drive gear).
2-pin plug for knock sensor I (between in
take pipes for cylinder no. 1 and 2).
2-pin plug for knock sensor II (between in
take pipes for cylinder no. 3 and 4).
2-pin plugon idle speed control (between
intake pipes for cylinder no. 2 and 3).
944 S2: between cylinder no. 1 and 2.
Plug for fuel injector ballast resistors (in
engine compartment at rear right next to
the plug for the brake pad wear
indicator).
2-pin plugs on each of the four fuel
injectors.
Because 944 S cars are supplied worldwide
since 1987 models with only one standard
control unit and said control unit is coded
accordingly depending an country
equipment, this coding must be checked in
case of complaint.
A 2-pin or 3-pin plug leads out at the DME
wire harness near the plug receptacle, in
order to be able to call the different curve
families.
Power is supplied to the DME control unit of
a 944 S via terminal 30 (b) in
addition to via ignition lock terminal 15.
DME - Diagnosing/Troubleshooting
Printed In Germany - XXI, 1989
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