two 625 PCMs shifting differently with the same chip

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Hello guys, my first thread here, hopefully it will not be stupid question.

I bough spare 16168625 PCM (with the lid at the picture). If I use my programmed chip (or original memcal from the PCM without the lid at the picture) in the spare 625, car shifting is weird. I think speed for 1-2 and 2-3 matches, but the shifting it very hard under any load. It kicks me to the back everytime. So I took it out and I'm affraid to use this PCM. The car is 1993 Chevy Astro AWD with 4L60-E, all is stock, only EGR is off in the bin. I did not changed any scalars or tables for 4L60-E.

My thinking is if this shifting behavior would happen only with my programmed chip, then it might be something I did wrong. But it happens if I plug the original BBMY memcal from my first 625 PCM too! So either there are differences in 625 PCMs, or the right PCM originally equipped with BHAS memcal is defective.

By the way now I drive my original 625 (without the lid) with G1 adaptor and using BHAS memcal (from PCM with lid) as knock sensor board without any issues. This way I can keep BBMY original memcal in glovebox in case of finding that my burned chip is not OK.

Is my thinking right and there is something wrong with my new spare 625, or are there really some differences between same number PCMs?

Attachment 14796

I had this happen, customer bought a "rebuilt" from NAPA and the circuit for the pressure control solenoid was dead.

Quote:

Originally Posted by In-Tech

I had this happen, customer bought a "rebuilt" from NAPA and the circuit for the pressure control solenoid was dead.

Thanks, I will check the schematics if pressure control solenoid section is repairable by me. If not, it might be still good enough PCM to run TH700.