Hopefully someone can help me on this one because it's been driving me crazy. When my car is in overdrive and even with the cruise on the torque convertor engages and disengages once every 2 seconds. This is a fairly new tranny with a 3200 stall, etc.. Anyway, If I click my manual TCC switch, it stays locked with no problem. Hence, at this point, I connect the Turbo Link to my laptop.
Everything engine wise is fine EXCEPT, the 4th gear and 3rd gear light are on at an idle. Even if it's in park. They come on and off at will. Sometimes, it's both of them, one of them, or either or. The TCC light is accurate when the TCC locks up. It blinks on and off every 2 seconds in true fourth gear and even in third sometimes?
I am totally lost. I have disconnected the 4 pin TCC connector to the tranny and it has not changed anything as far as the 3rd and 4th lights.(odviously the TCC cannot function) I have readjusted the TV cable, no difference to the readings or the TCC problem. I have changed out 3 different chips, with the exact same result. I have even changed the ECM today and have the same result. (note: ECM's are not easy to return)!
Has anyone ever heard of this? I need help.
Thanks
Allen
What speed and rpm is this happening?
This happens at any speed as long as the car is physically in 4th or 3rd gear. Usually around 65 because that is my usual cruise speed. It will go from around 2200 (tcc locked) to 3100 (stall speed) back and forth every 1.5 seconds. Extremely Annoying, however, if I click the switch, the rpm's stay low becuase the TCC stays connected until I release it with the switch when I slow down to around 45 or so.
One other thing. Until this problem happened. The TCC would ALWAYS engage in 4th gear and would not release REGARDLESS of how much gas I gave the vehicle UNLESS the car actually downshifted into 3rd. But when I let up on the gas, 4th gear would engage and the tcc would lock again almost simultaneously.
I had a similar situation on one of my Monte Carlo's, turned out to be the TPS. Since you have a scan tool, may be able to see if the TPS is stable at constant speed. Hope this helps.
I just replaced the tps. I figured that was the problem in the very beginning. Turned out the old tps WAS bad. The new one fully calibrated to correct voltages and works fine. But the problem did not change.
Your TTC solenoid is bad. I had the same problem. Any auto shop can change it for you.
There are two pressure switches on the valve body that close when the car is in 3rd or 4th. If the diaphram in them goes bad this can happen. They are dirt cheap from GM and easy to replace.When the switches close the ECM can lock up the TCC.