CarTalk.com Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

2001 Chevy Lumina - Slipping/Poor Acceleration

I have a 2001 Chevy Lumina (3.1L, sedan) with about 90k miles on it. I took it in to a local shop for mild slipping and a check engine light. I was thinking it might be something with the transmission but they weren’t able to find anything wrong with the that. They said the code was for a bad oxygen sensor and that I should get a radiator flush.



I waited about 2 months to replace the O2 sensor and the slipping did increase slightly over time. I had the car rescanned over the weekend and got the proper O2 sensor. The parts store also said that I had two EVAP codes which were probably from a gas cap not screwed on tightly. I replaced the bad O2 sensor yesterday and left the battery unplugged for a few hours to clear the code. My wife drove the car to work today and said that the slipping was worse than ever and driving up hills were hard to do due to lack of acceleration. When I’ve been in the car it seems like it’s not in the proper gear for the speed. I have a manual transmission in my car and hers sounds like mine would if I kept driving in 3rd on the Interstate. Also, the check engine light is back on…



Any ideas?

First thing to do is have the computer scanned and find out what code is being logged. Autozone will do this for free. I’m concerned that the previous “repairs” were little more than throwing parts after the code in the hopes that doing so would correct the problem. As you’re finding out, this rarely works.

I’d also suggest you take the car to another mechanic…specifically, an independent transmission shop. The problem you’re having needs an auto trans specialist’s attention. Stay away from chain places like Aamco, Cottman, Lee Myles, and the like.

Has the transmission had regular fluid and filter (if there is one) changes every 30K miles? How does the transmission fluid look and smell?