My car started chugging then the SES came on and the car died and wouldn't start. It gave a code 42 so I had the module checked and it tested good, put it back in and the car started right up but started running rough again after it warmed up but with no codes. I replaced the oem moduel just to make sure but it ran the same then a week later wouldn't start, I put the oem module back in and it stated right up. Took the new module back and it tested fine but they gave me anouther to make sure, again it would only start with the oem module which now tests bad? I checked all wires and conections and found nothing and still no codes unless I unplug something! This is driving me crazy, any ideas ??

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88 Formula 305tpi-at, headers, chip, free mods

 

Also all ignition parts are new . Could it be the distributor itself? IT looked fine but is their a way to test it?

 

42. Fault at electronic spark timing circuit OR
Fault at direct ignition system OR
Fault at fuel cutoff relay circuit

Recheck all your wiring to the ECM. I doubt the guys that were testing your module knew what they were doing, I don't think you can be 100% sure if it does or doesn't work... but I know that the one they sold you will always work and yours will always be bad :P It could be some bad connection causing the computer to not recieve data, a bad ecm could throw this code too.

 

I know the guy that tested the modules and watched him do the test so that isn't a factor. I'm going to try another distributor tomarrow. Is their a way to test the ecm ?