somethings not right

[Mr_Efficiency]

I have a 90 grand prix, 3.1 automatic (for now)

 

I'm having some small issues with my car, nothing serious but i want to stop it now before it gets serious.

 

Sometimes, not always but every once in a while when i start my car it will sound like total crap and struggle to run for a bit then die, if i rev it up and quickly put it in gear and start moving quick before it dies it will run fine, once its been moved under load its good to go. I think if i just rev it up it clears up to, I never try that cause my cars so loud and i hate reving the crap out of it in my driveway with the way my neighbors are.

 

The other problem, related or not i dont know but im guessing so. This dosent happen everytime but pretty often, if I'm moving along at a decent speed and the tranny shifts down and i hit around 3000-3200 rpms the motor will rev up and down between 3000-3200 until i hit the gas and it will down shift, rev to 4000 and take off no problem. it never does it around town, or not that i notice anyways, only when im cruising along around 80 km/h or so.

 

any ideas? thanks

 

[ManicMechanic]

vacuum leak?

[charged 3.1]

IAC maybe?

[1990lumina]

I'm assuming it's colder where you are now. IAC maybe be stiff/sticky. Happened with my Lumina..then I broke it cleaning it so it's brand new now.

 

The transmission thing is the torque converter unlocking and then locking again. If your engine isn't at operating temperature the torque converter won't lock - and when it sees the temperature dropping off again (due to air flow through the rad at highway speeds) it will unlock to allow the engine to run faster and warm up more. My Lumina always used to do this in winter, and it was accompanied by minimal cabin heat. New t-stat (195F) fixed that issue.

[rockfangd]

sounds like a possible IAC. and yeah the TCC likes to cause some problems

[Mr_Efficiency]

Ok good so its nothing serious or anything to be worried about, I was guessing TCC but wasnt sure, i'm not to farmiliar with automatics. I would have never guessed IAC but now that you say it sounds pretty obvious. and yes it only does it when its cold out, its been warm here the past few days and it hasnt done it at all.

I have another IAC so I'll clean it or change it and as for the TCC issue, i'm not going to worry about. the tranny has lots of quirks and i'd prefer a 5 speed and I found a good donar car at the local wreckers (89 GP) so I'm probly going to swap it anyways, I've done it to J and N bodies before, i cant see it being much diffrent other than getting around the weird subframe, but i found a write up on it that gave me a few tips.

 

Anyways, enough rambling, thanks guys

 

[Bake82]

Ok good so its nothing serious or anything to be worried about, I was guessing TCC but wasnt sure, i'm not to farmiliar with automatics. I would have never guessed IAC but now that you say it sounds pretty obvious. and yes it only does it when its cold out, its been warm here the past few days and it hasnt done it at all.

I have another IAC so I'll clean it or change it and as for the TCC issue, i'm not going to worry about. the tranny has lots of quirks and i'd prefer a 5 speed and I found a good donar car at the local wreckers (89 GP) so I'm probly going to swap it anyways, I've done it to J and N bodies before, i cant see it being much diffrent other than getting around the weird subframe, but i found a write up on it that gave me a few tips.

 

Anyways, enough rambling, thanks guys

 

 

There is no weird subframe. They are all the same. The only thing different between the auto and 5 speed subframe is there is a support bracket for the auto mount to go into, whereas for the 5 speed, there is no support bracket for the 5 speed.

 

It's pretty simple swap, and I think it could be done within a weekend..maybe two, aslong as you didn't do too much else to the car and just a simple swap.

 

If you need a hand let me know....I'm only in Ottawa so it wouldn't be that far to come up...however since you've swapped alot of them before you should have no problem doing the swap

[Mr_Efficiency]

Sorry, when i said "weird subframe" i was refering to the diffrence in the W body compared to those I'm used to in the J and N bodies. In those cars you only remove the driver side subframe, its not all one piece.

 

I dont know when I'm going to do the swap, I know the guy who owns the wreckers the car is in and i told him to hold it for me, all depends on when i get the $$ and the weather, its a swamp back there right now since all the snow melted and i have to pull everything myself. I have a decent sized garage so once i have the stuff home its a weekend job.

[rockfangd]

yeah the j and the n bodies subframe is totally different than the Ws