transmission

I have a 99 lumina ltz, the problem is when i hit the gas a little to hard , there is a chatter till i let off the gas. the car will not move very well. so if i let off the gas and hit it a little lighter it will then go normal . any answers. these troubles started after the local gm dealer did a trans tune up.

Does your car have traction control?

Check to see if the "cat" is plugged.

I have a '99 LTZ with traction control. Mine does this as well from time to time. Everynow and then, just briefly, the traction control light comes on. I have no cluse as to the problem. How would plugged cat cause this? It is something with a mechanical sound. It accelerates fine, just startling enough, you back off. Then it won't do it for a while.

My 99 GT does this, and it has traction control. It's just the way the 4T65 transmission operates. Try accelerating hard once without the traction control on ;) It's also not a good idea to accelerate real hard with the 3.8L motor. It has a lot of torque on the low end and can wreck your trans real fast.

Thanks BR.

I rarely drive the thing. I still run around in an old 180K 93 Astro. I have a '04 Avalanche, but rarely drive it. I will take the Lumina out for a spin tonight and into work tomorrow for the wife. She said she is noticing the traction control light coming on. Wierd thing is, I didn't know I had the option to turn it off. Will read the manual. She also said there is a whine coming from the right side. We have replaced the alternator before. I have a hunch that's what that might be.

You may not be able to de-activate the traction control on the Luminas. I don't know a lot about them, so I couldn't tell you for sure. In my 99 GP GT, I can deactivate it by pushing the TRAC button on the dash. There's one for sure way to do it though..and that's to pull the fuse :naughty:

Hey thanks!

It doesn't do it much, but when it does it is startling.