Buick Riviera

I have a 1986 Buick Le Sabre with a 3.8 TPI and 120,000 miles. Today while driving it started to cut out on acceleration from a stop then started stalling. It would restart easily at first but then got worse until it would not start, or if it did would not stay running. When it did start it would only run between 1000 and 2500 RPM, under it would die, over it would cut out and backfire through the intake. The car had a new timingchain installed 10,000 miles ago. It is getting fuel and spark. I also had just filled up with gas, but it had started cutting out shortly before that. I am thinking possible ECM. Anybody have any help. Thanks Leon
May 20, 2007.

IT may be a computer. Are there any codes I it?

When I hear the symptoms I think of a dirty IAC or egr valve. Codes would certainly help.

I am replying back on my original question to answer it for anyone else who has the same problem. I jumped the code and came up with a code 42-ignition control circuit. I talked to another mechanic friend and he said possibly crank sensor. Spent $47 and that didn't work. I thought the only other two things it could be were either ignition module or the computer. Went to junk yard and spent $20 on module and computer. Installed module car runs great and no more codes. These older cars and the crappy computers make you throw parts until something works. Thank god for junk yards. Also shucks took back the crank sensor that didn't help.

May 23, 2007.
Thank you so much for finishing off the post. Your effort will help someone. Gaurenteed.