1994 K1500

[shadowburt]

I am new to this "chat" thing, but I have a 1994 Chevrolet K-1500 4 x 4, that has two (2) different problems. When the "Service Engine Soon" light comes on, the thing shifts so hard it will take your hat off???

 

The "Service Engine Light" is intermittent, when it is not on , the engine rev's to approx. 3000 RPM, before the next gear shift.

 

I have read quite a bit about these problems on the net, but NO, resolve???

 

Isomeone could please help point me in the correct direction!!!

 

[99-2door]

Retrieve your codes from the computer. (Easy to do on the OBDI) Do a search for codes and instructions. The 4L60e can trigger the CES light with transmission codes also. Does it shift hard in every gear change or just a certain one? Anyway get those codes and we will be able to help you out more.

[GMC 1500HD Dude]

Get it to a good tranmission shop fast.

Let me guess, when you pull away for a dead stop, when it shifts from 1st to 2nd you get a hard thrust, as if you put in in netrul, revedd up the engine, and then dropped into gear?

I had the same problem on a 97' Sierra w/ 120,000 on it. It did the exact same thing. A guy in anther forum described it as a "bang 1 - 2". Apparently too much pressure is building up and it needs to be relieved. Thus, the thrust into 2nd gear. The relief valve needs to be bored out. I will try to find his emails and send them you.

One word of advise, get it fixed quick. I let mine go for about a week and it ended up costing me a complete transmission.

[shadowburt]

For all that may read this, there may be some GOOD News. I had it checked for codes today, and come to find out it was the TPS (Throttle Position Sensor) it was registering too low. No Tranny Codes

 

Thanks for the help and suggestions, and I hope that this may help someone else.