Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's, Olds 98 91-96, Buick Lesabres and Park Avenue 91-96. Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
Hey guy's help me get this car fixed. Ever sense replacing engine earlier this year, it has run sluggish above 50mph. Below 50 you cant ask for a better running car. Only CEL it has is from not having cat anymore, but it ran the same way then also. It's been tuned up, ICM changed, new crank sensor, MAP, fuel pressure reg and so on. Could the PCM be causing engine to run bad? Also the transmission seem's to want to shift way too soon. I have a TPS I can try in the morning. Please help me save my car from trade-in.
Sony MDX-C7900 running thru Bose system-CD changer in trunk-XM-Infinity tweeters. Autolite APP 605 plugs. New left lower control arm. New water pump, ICM, Crank sensor, MAP,TPS. Working on 2nd engine. Adding to car all the time.
Tried the spare I have, no change. Unplugged the TPS but tranny quit shifting so plugged back in. Will try spare TPS to see if that helps. When engine was changed out, dealer didn't mess with PCM wonder if maybe they should have.
Sony MDX-C7900 running thru Bose system-CD changer in trunk-XM-Infinity tweeters. Autolite APP 605 plugs. New left lower control arm. New water pump, ICM, Crank sensor, MAP,TPS. Working on 2nd engine. Adding to car all the time.
Try cleaning the MAF sensor, and make sure the intake air temp. sensor is working.
The engine does need some backpressure to get torque. This occurs in low-RPM situations such as on the highway. At 50 mph the engine is turning ~1300 RPM, IIRC. So running without a cat could be having a deleterious effect.
If you were going for fuel mileage, people would kill to have their transmissions shift sooner!
2012 Chevrolet Cruze Eco - Current car
1999 Buick LeSabre Custom - Former car
Learn from the mistakes of others, that way when you mess up you can do so in new and interesting ways.
If my PCM does need a case learn, how do I do this?
Sony MDX-C7900 running thru Bose system-CD changer in trunk-XM-Infinity tweeters. Autolite APP 605 plugs. New left lower control arm. New water pump, ICM, Crank sensor, MAP,TPS. Working on 2nd engine. Adding to car all the time.
Anyone with an HPTuners or a tech II can do case learn to my knowledge. Probably other programs will work, but I don't know what all else. The stealership can rip you off, unless you can get them to do it for free. The process takes a minute at best.
TPS helps control the shift timing.
Did the transmission get replaced when the engine was replaced?
I have a Bonneville, it's white and N/A!
Mod List: Hood and Fender "adjustment" - "Enhanced" A/C compressor clutch - Extra loud PS Pump - Mega sensitive CKPS - Audible Rear Drums - Lowered headliner - Custom stained upholstery - "Brown Devil" weight reduction kit - Low Friction Belt. More to come!
No new tranny when I made the swap. Got a gut feeling I might need a case learn. Will call around for best price.
Sony MDX-C7900 running thru Bose system-CD changer in trunk-XM-Infinity tweeters. Autolite APP 605 plugs. New left lower control arm. New water pump, ICM, Crank sensor, MAP,TPS. Working on 2nd engine. Adding to car all the time.
Hey guy's help me get this car fixed. Ever sense replacing engine earlier this year, it has run sluggish above 50mph. Below 50 you cant ask for a better running car. Only CEL it has is from not having cat anymore, but it ran the same way then also. It's been tuned up, ICM changed, new crank sensor, MAP, fuel pressure reg and so on. Could the PCM be causing engine to run bad? Also the transmission seem's to want to shift way too soon. I have a TPS I can try in the morning. Please help me save my car from trade-in. 
wonder if maybe they should have.
If my PCM does need a case learn, how do I do this?
