Need help, injector pulse

[stevo82]

Hey guys I seriously need some help. I took my car in for a head gasket and water pump replacement. After the guys finished the car (ep82) didnt want to start. After searching we found that there is no pulse on the injector plugs. When ignition is on, the positive wire works, but nothing we do gets the earth wire, which we assume sends the pulse, to work. I get an error code 22, but seems that has nothing to do with the injectors.

If we disconnect only one injector plug, both its wires give power. We're really stuck here, dont know what to do. I see on the ecu there is 2 pins for the injector pulse. Can I run a wire from those pins directly to the injectors, bypassing any bad wiring? And where is the ecu located?

Please guys, I really need my car, I'm desperate! Thx!

 

[stevo82]

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[Texx]

When ignition is on, the positive wire works, but nothing we do gets the earth wire, which we assume sends the pulse, to work.

Your right, the ECU grounds the injector circuits to pulse the injectors. How are you checking for an injector pulse? Are you using a multimeter or an oscilloscope? If using a meter be certain it's update rate is quick enough to indicate an injection pulse and only carry out a continuity to ground check. If you try and check for voltage between a battery live and injector pulse wire, you'll risk damage to the ECU.

I get an error code 22, but seems that has nothing to do with the injectors.

Are you sure it's code 22 (open or short in THW signal) and not code 12 (no Ne or G signal to ECU)? If the ECU does not receive a Ne or G signal from the distributor it will not fire the injectors or ignition coil. Have you checked for a spark?

If we disconnect only one injector plug, both its wires give power. We're really stuck here, dont know what to do.

If you are checking injector No.1 connector you'll need to also disconnect No.3 connector or you see a battery voltage feedback on the ground terminal, the same with No.2 and No.4. Your best off disconnecting all 4 injectors when checking for a battery live or you will get confusing readings.

Can I run a wire from those pins directly to the injectors, bypassing any bad wiring?

I wouldn't recommend that unless you have tested the stock wiring and found a fault.

And where is the ecu located?

The ECU is located behind and below the radio.


The ECU takes a ground from the intake manifold, it's worth checking it's been reconnected.