Howto test ECM?
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Car: 1992 Chevrolet Camaro RS
Engine: 305 T.B.I.
Transmission: 700R4
Axle/Gears: 2.73 Open Diff
Howto test ECM?
I tried searching the forums but found nothing. The car will start only with starting fluid and than the injectors take over and it will run until it warms up and hits closed loop mode it sounds like. I have checked all the sensors and it seems to be a problem that no one knows. I can't figure it out. I tried a different ECM but the same thing happens but that ECM could be bad also for all I know.
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Car: check
Engine: check
Transmission: check
Re: Howto test ECM?
Many times this is from a lack of fuel pressure. It could be that the pump is weak or the filter is clogged. It can also be caused by fuel pump relay being bad.
Connect a fuel pressure gauge and at key-on, engine-off (KOEO) the fuel pump runs for 2 seconds and builds to between 9 and 13 psi (TBI). If the pump doesn't run at KOEO then look into the pump relay circuitry.
Then while running the pump maintains that pressure. If the pressure is low then need to troubleshoot why.
RBob.
Connect a fuel pressure gauge and at key-on, engine-off (KOEO) the fuel pump runs for 2 seconds and builds to between 9 and 13 psi (TBI). If the pump doesn't run at KOEO then look into the pump relay circuitry.
Then while running the pump maintains that pressure. If the pressure is low then need to troubleshoot why.
RBob.
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Re: Howto test ECM?
What kind of car is this?
I've had a couple now, that had VATS/PASSLOCK issues, and starting the engine on starter fluid and running it for the first 20 seconds or so off the starter fluid would then get the ECM to enable the injectors.
If you've swapped the ECM, with the same result, I'd say look elsewhere.
I've had a couple now, that had VATS/PASSLOCK issues, and starting the engine on starter fluid and running it for the first 20 seconds or so off the starter fluid would then get the ECM to enable the injectors.
If you've swapped the ECM, with the same result, I'd say look elsewhere.
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Car: 1992 Chevrolet Camaro RS
Engine: 305 T.B.I.
Transmission: 700R4
Axle/Gears: 2.73 Open Diff
Re: Howto test ECM?
1992 Camaro RS 305 TBI. The computer I put in could be bad. I hear the fuel pump prime every time but the injectors will not start themselves. I will post again once I get a gauge and test fuel pressure. It is a very odd problem.
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