Yep.

 

It can come on at any time, but usually after you have been driving for a while. It then shifts really hard and stays on again usually until you stop the car and shut off the engin for awhile. I started to measure the time it comes on by mileage and days and it comes on about every 200 miles or about every 3 days.

 

Knowing the trouble code that is being set would help.

 

Okay, T/C light on and hard shifts is sort of like the old "limp mode" and could be a number of things. Without any check engine light and the codes stored when that happens it gets harder to track down. Have you had it scanned for codes? Local autoparts may do this for free......

Likely suspects are cam position solenoids, (there is a thread here about replacing them) a disconnected, or oiled MAF sensor. (only oiled if you have an aftermarket air intake with oiled filter) MAF sensor is right at the front of the engine on the air intake...... Guys at quicky lube places often forget to hook these back up after not being able to figure out how to change the air filter..... I'm sure there are other possibilities having to do with engine management that will put the car into this "mode" but I'm just going by what I've read here on the forum.

With it being intermittent I would not think MAF and would lean more towards the solenoids. Before you start swapping parts though see if there's any stored codes.....



EDIT: ChevyMgr beat me to it again.......

 

Thanks for your help. I am taking it to the dealer on Thursday. Someone else said it might be a 'Exhaust Cam Actuator' . I'll find out for sure on Thursday. Too bad I didn't wait a year to buy as the 2007 changes to the 5 yr 100,000 mile warranty!

 

Yep, this is what was happening to Blackie. Finally got tired of it and took him in and was told it was fixable and extended warranty covered whatever it was.

Something about a sensor, but i know nada about cars, so no help, but it was an easy fix it seemed.

Good luck!

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