blue94

To say I am at a loss is an understatement. Last week I noticed that my 4l60e with a PI Vigilante TC was not going into lock up so I hooked up the computer and did a Datamaster log on it. The TCC Enable, Engaged and Control all change to 1 at the correct time but the converter does not lock when the active gear is D4 (used brake to test).

After un-hooking the computer I took it out and now it locks as it should (WTF, no changes made).

I have checked the obvious items, brake switch, trans switch, etc. only things left that I know are the harness or the TC itself. As the harness is not cheap and pulling the TC is not fun does anyone know how to test those before I drop some coin and/or do a lot of work.

The TC is still under warranty so I will call PI but i am out of ideas.

Thanks!

383vett

I don't quite understand. You said after you unhooked the computer, the torque converter locks up? Without the computer the tranny would not shift or lock up. If somehow it did, that would eliminate the torque converter. What you can do is go through the schematic and see which wire in the harness is the tcc (torque converter control) wire. Splice into that wire and take the car for a drive. Ground the wire in 3rd or 4th gear and the converter should lock up. If it works, then the converter is definitely ok and work backwards to figure why that wire does not ground when it should. You can always hook up a switch on the console to ground the wire and use the converter as a 5th gear on the freeway. That's what I did.

blue94

Sorry, I should have said the PC running datamaster and not computer. I just got off the phone with PI and their tech said to try this test.

remove the lockup solenoid and put in a 5/16 check ball.
put the solenoid back on, button up the trans pan add fluid.

Then start the car and put the car in gear, if the car dies "like you bogged a manual" the TC lock up and front pump are fine now focus on the solenoid as the problem.

Going to try and get to a lift in the next day or two to try the test, will let you know how it works.

pologreen1

WOW this sucks good luck with tracking this bug down

NitroNutt

make sure brake switch is adjusted correctly.