Code 42

[1988GTU]

Can someone help me understand the code 42 a little bit better?
3.1MPFI L body (Use to have 2.8MPFI) auto trans.

I know it has to do with electronic spark timing, but what part(s) would need replacing if this code shows up. It would come on when did the following: Start the car cold, let it get to operating temps, shut it off and restart it. Light will be on during second start.

[1988GTU]

Would extending coil/ign. module harness wires have any effect to throw this code? Granted, the harness wires are together by soder.

[FastGT31]

did that code ever show up before you moved it? if not it could be a cold solder joint. a faulty ignition module could also throw that code as well as a bad ecu (worst case). if you moved the coil packs, where did u relocate them?

[1988GTU]

Pass. side on a metal bracket attached to the fender structure.

[Doubt_Incarnate]

dont rule out the crank position sensor. the important thing it seems when relocating the coils/module is to make sure it is grounded properly. it used to be grounded through the engine block, if you move it you need to make sure that not only the connetors reach but the actual assembly is grounded good.

[1988GTU]

So what would need to be done to the CPS to give is a nice ground? Cut splice into its harness?

[Doubt_Incarnate]

i should have typed better.

the cps is one of the potential problems.

i'd start by making sure the the coils/module is bolted down to something metal or a wire ran from the mounting bolts to a chassis ground. if you rembemer the coils sit on the module, and the bolts for the coils run throught the module and screw into the aluminum mounting plate. its important you ground that plate.

[1988GTU]

So I will have to run a ground strap/wire from that bracket on the back of the ign/ module to the engine? I would have thought when I touched a wire from that bracket to a engine bolt it would have turned the SES light off.

[1988GTU]

Oh and I only get a code 42... Would that CPS be the same code?

[Doubt_Incarnate]

probly not the cps then, im not 100% sure but it would probly have its own code.

just make certain that the bolts holding your bracket in go thru clean bare metal holes. mainly where the module bracket meets the metal of the car.

if your happy with the connections and the grounding then you should move on to seeing if there are failed parts.

[1988GTU]

This sucks. Thanks for the help... If you have any more ideas throw them out in here!

[tractorman]

why would you relocate the coils?

[1988GTU]

Easier to get too. Keeps the heat away from the exhaust manifold. Keeps weather/road debris from finding it. It's been done many times, just don't know why this one is being so much of a PITA!

[Doubt_Incarnate]

hayes performance, (SP?) has relocated his, talk to him to see if he had a similar problem. there is always the possibility you stirred up trouble moving things around and an underlying problem surfaced.

[1988GTU]

Okay thanks.

This car is a problem child.