87 Dodge Lancer

How can I tell if the Logic Module or power module itself is bad? The car refused to start although it would crank. I noticed that the Power Loss lamp was not on when ignition was turned on. Replaced the bulb and for a short time it showed only 55 (end of codes). Then it refused to come on although the bulb was fine. I checked the timing and it was at zero degrees. The fuel pump/regulator/injector all test fine.

Reply to
Eddy351
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Tried a different logic module and power module but same thing happened. (Could be bad replacements, got them at a junk yard)

Reply to
Eddy351

\ Basic's!! fuel spark and compression, which one don't you have and start from there. Try spraying an injector cleaner or some kind of spray that will burn into the throttle body, see if it starts and dies.

Glenn Beasley Chrysler Tech

Reply to
maxpower

Thanks Glenn, with a little starter fluid it finally kicked to life and ran while I reset the timing (which got monkeyed up during my various machinations). BUT the power loss lamp still does not come on. I checked the output right near the logic module by making a small nick on the wire out of pin 4 of the white 25 way connector (per the service manual) and the signal ground but voltage was about 0.6 V. I checked the bulb and continuity so I know there is no break/connector issue in between. Could the logic module be bad? I got it out of the junk yard and it has the same part number on it as my original (5233372). Clearly some of its outputs work fine but the error code function does not seem to be functional.

Reply to
Eddy351

really without seeing what the vehicle did as it wouldn't start would be hard to say what it was. Was it just because it was flooded?

Glenn Beasley Chrysler Tech

Reply to
maxpower

it certainly acted like it was flooded--started when pedal was floored.

but it is still not right ---power loss light does not come on, which makes me wonder why it did not start last week, and all the cranking since that time probably flooded it. The injector seems to be squirting more than normal amounts of fuel when I turn ignition on--but it could be my imagination. Could pulse width of signal to injector be affected by a malfunctioning computer? (not sure which computer).

The replacement logic module seems to be working right but the logic module seems to be sick-no power loss light. The replacement logic module has the same part number as my original--could it be coincidence that the second unit was also bad? The junk yard clearly had no way of testing it but is willing to replace it.

In the 19 years I have lived with this car, I've seen nearly everything but this one has me puzzled. Really appreciate your help!

Reply to
Eddy351

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