New Pcm

I am planning to install new PCM in my 97 3.1L, I will try to get one from the Auto Zone. But, my concern is will I be able to install one without any type of reprogramming, I know the trick with password relearn (After installing new PCM attempt to start the car, leave the key in ON position until “theft system light” stops flashing after 10 min. “ but I am not sure if that is enough. Also If new PCM does not work and If I try to use my old PCM again will I have any problems with starting my car?

It might work with the 10 min relearn but sometimes you need a tech II scan tool.

If the new one doesnt work then you shouldnt have any troubles putting the old one back in.

Why are you replacing the PCM anyway ??

it could have bad driver for some of my injectors and causing misfires on only 2 cylinders. No mechanical problems with cylinder heads (valves and seats or springs or head gaskets), no vacuum leaks, icm, coils, wires, spark plugs, egr are all good, fuel pressure is in specs, all injector grounds are good, but oxygen sensor cross counts sometimes drops to 0 and sometimes go up to 12 counts. Today I just wanted to see how much voltage is at the pink power splice (after 10 way injector connector) that should provide 12 v to all injectors with ignition on or engine running, so with KO I got battery voltage, with ER I got 11.14 V. I know that all injectors are good unless for some reason injectors 3 and 4 get so hot to increase their resistance and cause misfires. I will try to jump it with a thicker wire from the same F/P and Injector fuse to that splice to see if that will help.

just because the injectors are gtting 12v doesnt mean they are working properly.

They could be clogged or just faulty.

Check the resistance when they and the engine is COLD.
This has all been gone over before.
If you do a search in the GA or N-body forum
you would find threads with the exact same question .... :shakehead