I am wondering if part of the problem is that the PROM in the computer became defective. Yes, I know these things don't tend to go bad but I am reaching for straws. I am seeing a lot of PROM chips being listed on eBay that claim they can be used in my '93 Buick LeSabre even though they were pulled from other cars. Yes, the computer number is the same, 16141470, but there are different PROM letters. What would be the difference between a 1993 PONTIAC BONNEVILLE and my 1993 Buick LeSabre? The guy is claiming the same PROM will work for both. My computer has the BCBY beside of the 16141470 so I am guessing that is the PROM number/letters.

I am seeing this guy with several PROMs all claiming to work in my 1993 Buick LeSabre even though they came out of different cars, like the Pontiac Bonneville, or 1992 BUICK PARK AVENUE.

BDNT, BDMU, AXDH, to name a few.

Normally if you have a bad PROM after resetting the ECM(unhook battery for a few minutes) you will get a code 51.

Thanks, I looked that up. Plus, I did some reading on the PROM. The PROM may be out of calibration (unlikely but possible) but it is not bad bad. I guess I will continue my problem over in the original thread on that.