Need help diagnosing auto tranny problem!
#1
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Need help diagnosing auto tranny problem!
It's in the Cobalt with a 4T45E 4-speed automatic. The problem started this past weekend and has been consistent since then. Here's my issue:
While in D, the car will sometimes rev to 4k rpms in 1st gear before shifting to 2nd, even while under normal driving. In I, the car seems to shift slowly from 2nd to 3rd under moderate throttle and that causes the engine to rev to 5k RPMs by the time it shifts into 3rd... And finally, when in L, the car will carry up to redline in 1st just fine, but when it goes to shift into 2nd it'll stay at redline and slowly accelerate until it finally shifts into second and then continue to accelerate hard up to redline.
I had installed an Auxilliary transmission cooler in March to try to keep the transmission cool and healthy, but I've heard that that can sometimes hurt more than help. So today I disconnected it from the circuit, but the problem persists...
Please help!
While in D, the car will sometimes rev to 4k rpms in 1st gear before shifting to 2nd, even while under normal driving. In I, the car seems to shift slowly from 2nd to 3rd under moderate throttle and that causes the engine to rev to 5k RPMs by the time it shifts into 3rd... And finally, when in L, the car will carry up to redline in 1st just fine, but when it goes to shift into 2nd it'll stay at redline and slowly accelerate until it finally shifts into second and then continue to accelerate hard up to redline.
I had installed an Auxilliary transmission cooler in March to try to keep the transmission cool and healthy, but I've heard that that can sometimes hurt more than help. So today I disconnected it from the circuit, but the problem persists...
Please help!
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Ugh.. I have an AutoX this weekend and I was all set to go, but if I'm having these kinds of issues, it's obviously out of the cards...
This was one of my greatest fears as well... Now I've got the thought in my head of looking at getting rid of the car and just buying something that's stock...
This was one of my greatest fears as well... Now I've got the thought in my head of looking at getting rid of the car and just buying something that's stock...
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Bump... Is this something I'm going to have to take it to the dealer for? I'd really rather not have to pay $85+ for them to diagnose the problem...
Last edited by Illini_06SS; 06-02-2010 at 07:56 PM. Reason: Automerged Doublepost
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I jacked up the front of the car just enough to squeeze my arm underneath to loosen the check hole (the transmission is almost perfectly level) and when I did so, oil came bursting out. The transmission is warm, but not hot (the oil didn't burn me), I'd say it's 130 or 140 degrees F.
Would being that warm result in THAT MUCH fluid expansion? Do I somehow have an overfilled transmission (was prefilling the auxilliary cooler the wrong thing to do?)???
Would these problems be symptoms of an OVERfilled transmission?
Would being that warm result in THAT MUCH fluid expansion? Do I somehow have an overfilled transmission (was prefilling the auxilliary cooler the wrong thing to do?)???
Would these problems be symptoms of an OVERfilled transmission?
#9
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Its supposed to be running in Nuetral when you remove that plug.
Thats the reason it seems overfilled.
Start the car and fill it up to the check hole.
Thats the reason it seems overfilled.
Start the car and fill it up to the check hole.
Last edited by Cherry GT; 06-02-2010 at 08:53 PM. Reason: Automerged Doublepost
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I redid the test with the car running and the tranny in neutral and only a little bit of oil trickled out. Maybe an ounce. It's definitely full. It may be slightly overfull, but not by more than at most another ounce.
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The transmission is warm and seems up to temp, don't know the exact temp because I don't have access to a scantool. It's certainly not cold.
Last edited by Illini_06SS; 06-02-2010 at 09:15 PM. Reason: Automerged Doublepost
#15
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You could have put one on the feed line to the cooler that you installed. You put a supercharger on your car, it can't be much harder.
I'm curious if the dealer notices anything. I say there is a good chance they think it's stock, besides intake/exhaust. You have the supercharged badges, so it must have came that way
I'm curious if the dealer notices anything. I say there is a good chance they think it's stock, besides intake/exhaust. You have the supercharged badges, so it must have came that way
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