I was haulin a Chevy Blazer on a car hauler in my truck as spec'ed below in my sig....and when i was in drive and overdrive I noticed a pattern to my torque convertor lock. It would lock for 4 seconds, then unlock for 4 seconds, then lock for 4 seconds, then unlock for 4 seconds, etc...every time it would unlock my RPMS would go up by about 400-500 RPMS....It got to the point where i would know when it was comign and let off the gas when it would unlock. what would cause this? i think maybe 2 or 3 times when it shifted into OD the torque convertor didnt unlock and I could steadily stay on the gas. what causes this?

 

Throttle position sensors have been known to cause this problem. Do a search for that topic and I'm sure you will find a more in-depth explanation.

 

If your TPS checks out fine, I would check the brake light switch next. Does your cruise control stay engaged? Does it kick off on it's own? A bad brakelight switch will make the tc lock and unlock. As soon as the plunger on the switch looses it's indents, the problems start...lol.

But so will a bad/misadjusted TPS. Usually you can replicate the problem by holding the pedal in a certain position.


Good luck.

 

do you have any stored codes? you can use the key on-off-on-off-on method and the codes will be displayed on the odometer. some codes dont throw the CEL light.

 

I replaced the TPS several months back and the problem didnt go away. I have CE codes but my Hypertech programmer read them off as being the oxygen sensor. I have a trailer brake package installed, etc....so where do I find this faulty brake light switch?

 

under the brake pedal... if you poke your head under there you should see it. it'll be activated as soon as the pedal leaves its normal position. (at least thats the way it was on the last 2 cars/trucks that gave me brake light problems)

 

funny how something like that can cause a torque convertor to do that. is it really hard to replace?

sorry about all the questions guys, im totally stupid when it comes to mechanics, etc. but hey, if any of you all ever have computer problems I can help ya out, lol.

 

should be easy, have you downloaded the manual from the merry christmas thread? (located within the threads at the top)

 

yup sure have. I"m sure I'll find the brake switch thing on page 300 million of the manual... lol

i went to print it off without looking at how many pages it was....the next day i woke up and thought it was done, it was just askin for more paper so i put a whole ream of paper in it...the next day same thing, not even 1/10 of the way through and was still beggin for paper...lol

 

yeah it's better to just leave it on the comp, it'll kill a tree printing it out. I usually print out the pages that are relevant to what I'm working on if I need them in the garage.