So i posted this same question a week ago. My wife drives the cavalier to work everday, and i just got a chance to see what she was talking about. I just took our new 01 2.2 on a 700 mile trip with no problems just when i started to think she was crazy the tranny started slaming into gears. Normally the car shifts great. I came to a red light and when i went to take of it dragged ass in first than slammed into second an so on. The traction off indicator came on. This happend from to stops, and take offs then went back to shifting smooth as butter. I want to get this resolved for one it cant be good on the tranny, and two i dont want the wife and kids pullin out in front of someone and not being able to take off. Also one in awhile, when i take off the engine bogs down and hesitates. I gave the car a tune up and still happens. I dont get it the the motor idles nice, even seems a little high to me since you have to keep a sturdy foot on the brake so you dont roll off. Please Help! You guys know these cars much better than i do!
I'm assuming this is a 4spd automatic. (Will have PRND321 on the shift selector).
If that's the case as funny as it sounds, change the IAT (Intake Air Temp.) For some reason, when these are bad, or even just unhooked the transmission will slamshift, most noticeably on the 1-2 upshift. If you don't know where the sensor is, it's in the intake tube about halfway between the throttle and the airbox.
i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick
It is a 4 speed. I did just post that i thought it was the IAT because i started my Z24 up without it plugged in and it freaked me out. But in my last post a few people said this trany is set up differnt" vacume" controlled. I dont know too much im mostly a parts changer lol. Have you had a 4 speed act up because this sensor? I was planning on trying it anyway since the parts fairley cheap.
If it's a 4spd it's electronic. If it's a 3spd it's vacuum controlled.
I've not had a trans. act up because of this, because i've always had the 5spd. But i've been around here for a while and been through many a posts from kids with this problem because they put an intake on, and did not put this sensor in with it. Gives you the same problem.
i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick
Looked up your other post. You stated in the other post that you have a 3t40.
If you have a 4spd you have a 4t40, which is electronic.
If you have a 3spd then you have a 3t40, which is vacuum.
i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick
I thought this sounded familiar.
Hmmm, I should try this, bc my 00 Z shifts hard from 1-2 and again from 3-4. That part is relatively cheap. But wont it throw a code if its going bad, or no??
Yes i have a 4 speed. Shifter is like you exsplained. I just thought it was a 3t40 e because its a base model. This trans is a total dog thought. takes forever to shift unlike my Z24. Maybe it just set up differnt for the smaller motor. I searched other places and heard of a bad speed sensor or trouble with the wiring to it. I dont know im gonna replace the IAT sensor i will let you know what i find
Well... according to your other post you weren't sure about the trans fluid. I believe I suggested having it changed. My Trailblazer was giving me a bit of a harsh upshift from 1-2 and it went away for the most part after changing the fluid/filter.
If it's taking a long time to perform a shift, I would suggest even more to change the fluid. If that's what it's doing there is, I believe, a timer on the computer. Once this time has run out for the shift and it's not finished shifting the computer will ramp up the line pressure by a lot. This will make it snap into the next gear pretty good. I was able to do this with my GTP by flooring it between a 1-2 shift at the right speed. It would boost up and slip, the computer kicked the pressure up and the thing squawked the front tires really good when it finally hit 2nd gear.
i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick
A hard 1 to 2 shift can also be a symptom of a trans going out. The clutches cant grip when the trans heats up so the computer kicks up the line pressure and wham shift.
Well the car only acts up once in awhile. Like i said it shifts pretty smooth, and once in a blue moon the traction off light comes on at a take off it slams through a couple gears then goes back to shiftin smooth. I dont think this is a mechnical problem what so ever. Something electrical is momentary messing up. I just went on a long trip over 600 miles, and it was fine. I got home and it did it later that night.
Ok so my shifting got worse it started happening all of the time and the car kept dying. Engine light came on so i ran the codes, came up with the throttle position sensor. I replaced it for $30 and have not had a problem. The old sensor was worn, and spun all sloppy. Thanks for the help hope this is the end of this problem.
