ZR1 prom code chart

[tpr60]

Talked my friend into buying a 90 zr1 Tuesday, pretty nice car with 103k miles. It came with an extra prom in the glove box with a code of AUAH8555, I can't find my chart or one on the net site. Is this a 1st design prom or the updated 90 prom? I haven't checked the prom in the car yet but suspect it not OEM. Any one have accesses to a prom chart.

[scottfab]

That AUAH8555 sounds like the stock chip for a 90.
There was a TSB 476503 that updated that chip
to 16163905. The new chip corrected a problem where
the idle would not return to normal fast enough after
coming to a stop.
This was found on some old email from 1999 so
it could be dated now.

[tpr60]

Thanks Scott, I knew about the update but couldn't find my notes. Is there a prom chart available in any of the net posts?

[scottfab]

Can't find a table but that does not mean one does not exist.
There is a poll on who uses what chip. That likely would however not have the granularity you need.

[WVZR-1]

This is as close to a complete PROM ID CHART that I've ever seen. It's from a Tuner Cat Program and the information seems to be consistent with GMSPO information:

LT5 PROM INFO.png

There would be no reason to remove it to ID it. The scan ID that's in this chart should be what's displayed on a Tech1 or suitable scanner. Now if it were thought to be a modified PROM then ??

[tpr60]

Wow! good chart. THANKS!! I am sure this will come in handy for a lot of others to.

[scottfab]

Originally Posted by WVZR-1

This is as close to a complete PROM ID CHART that I've ever seen. It's from a Tuner Cat Program and the information seems to be consistent with GMSPO information:

Attachment 3432

There would be no reason to remove it to ID it. The scan ID that's in this chart should be what's displayed on a Tech1 or suitable scanner. Now if it were thought to be a modified PROM then ??

Great find. Very helpful