I am working on swapping a '92 legacy turbo motor into a 95 impreza. I've been moving it in and out of the garage and the other day it died and wouldnt restart. There's no CEL with the ignition on like there should be and the ignition relay clicks very fast. The tach also jumps to 1500 RPM with key on. All fuses and fusible link are Ok. I am thinking the ECU is toast. Anybody have any ideas?
Thanks,
-Jim
EJ22T engine into Impreza electrical problem
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vrg3
- Vikash
- Posts: 12517
- Joined: Sun Nov 03, 2002 2:13 am
- Location: USA, OH, Cleveland (sometimes visiting DC though)
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This does sound like it might be a malfunctioning ECU. The Check Engine light not coming on especially. The ECU does have a self-shutoff control that controls the ignition relay too. The tach is driven by a signal from the ECU, as well.
Like Mark said, it could easily be a low or dead battery. The ECU needs about 9 volts to function; if system voltage falls below that, the ECU won't be able to do its job. If the draw of the ECU and sensors is just enough to bring the voltage below that threshold, then it would cycle on and off.
Do you have ABS? If you do, the ABS light usually comes on when system voltage is low, since the ABS computer needs 9 or 10 volts too. You can check your battery's voltage with a voltmeter.
If the voltage on the battery is below 11 volts, you may not be able to revive the battery at all, since one of its cells is likely sulfated. In any case, an overnight trickle charge, like Mark said, is worth a try. A plug-in battery charger is a good investment for 30 or 40 bucks. I got a Diehard one and have used it many times. The car's charging system is only meant to keep a battery charged, not to recharge a flat battery.
I guess it could also be a bad ignition relay.
Does the engine crank and not start, or does it simply not crank at all?
Like Mark said, it could easily be a low or dead battery. The ECU needs about 9 volts to function; if system voltage falls below that, the ECU won't be able to do its job. If the draw of the ECU and sensors is just enough to bring the voltage below that threshold, then it would cycle on and off.
Do you have ABS? If you do, the ABS light usually comes on when system voltage is low, since the ABS computer needs 9 or 10 volts too. You can check your battery's voltage with a voltmeter.
If the voltage on the battery is below 11 volts, you may not be able to revive the battery at all, since one of its cells is likely sulfated. In any case, an overnight trickle charge, like Mark said, is worth a try. A plug-in battery charger is a good investment for 30 or 40 bucks. I got a Diehard one and have used it many times. The car's charging system is only meant to keep a battery charged, not to recharge a flat battery.
I guess it could also be a bad ignition relay.
Does the engine crank and not start, or does it simply not crank at all?
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vrg3
- Vikash
- Posts: 12517
- Joined: Sun Nov 03, 2002 2:13 am
- Location: USA, OH, Cleveland (sometimes visiting DC though)
- Contact:
Ah, yes, grounds, grounds, grounds!
My brother and I are planning to rip out every inch of stock wiring in his Mark II Supra and replace it with our own properly-done wiring. I have half a mind to run separate negative wires to every circuit that may need it rather than just relying on the mechanical mounts and chassis to complete the circuit.
Good to hear your engine's running again.
My brother and I are planning to rip out every inch of stock wiring in his Mark II Supra and replace it with our own properly-done wiring. I have half a mind to run separate negative wires to every circuit that may need it rather than just relying on the mechanical mounts and chassis to complete the circuit.
Good to hear your engine's running again.