4L60E Shifting Issue

[blkvette85]

I have a 94 1500. Replaced a leaking output seal and changed the fluid. Truck ran great. About a week ago, a cooler line broke. Fixed.

Now, the trans is holding first gear until about 4000 rpm. I have been told it could be anything from the throttle position sensor to the ignition switch,

Any ideas as to what could be the problem or where to start checking?
Thanks

 

[NacIK]

The ignition switch problem refers to the power to the transmission solenoids. If there is no power the transmission will only shift between 2nd and 3rd manually. If the shift indicator LED is lit then it is getting power and that is not the issue. The TPS could be the problem. I had the same problem on mine when my TPS went out. I hooked up the scan tool and it was not putting out a signal between 15 and 25 percent and would not allow it to shift up.

That said I think there is a connection with the fluid change. A solenoid might be sticking or your trans might not like the brand of fluid. Try to use some Lucas transmission shift lube. Try about 4 oz and see what happens. It usually does the trick for me in a pinch.


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[NacIK]

I forgot to ask. Do you know why the line broke?

I am sure you checked, but just in case was the trans fluid at level and free of coolant?


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[blkvette85]

The cooler line had a rubber hose spliced in. Broke at the rubber connection.

I put a TPS in about a year ago. It could be a bad, got it at Autozone. No check engine light, no codes.

I swap out the TPS and see what happens.

Thanks

 

[oohunter04oo]

I'd bet You are low on transmission fluid.... The transmission in My 94 leaks into the transfer case. So when it starts taking forever to shift into 2nd I know it's low.

 

[NacIK]

That's what I am thinking. Just being a little off either way or by having fluid that is slightly different than OEM will cause issues. My trans didn't like Royal Purple for some reason. I drained it out the hard way to save it and then bought the GM stuff to put back in. I haven't had a problem since.


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[highspeed]

I know my MAF plug was loose and would cut signal sometimes, and it caused my transmission to shift weird. Probably a different issue for a 94 though

 

[blkvette85]

swapped out the TPS sensor, no change. Don't think it's a fluid issue, ran fine for about a week after the cooler line broke.

 

[highspeed]

So no CEL?

 

[blkvette85]

Nope. Just doesn't want to shift. Thinking something burned up when the line broke.