1994 Ford Explorer Automatic Transmission (160K miles) is always engaged. The explorer 4.0 liter engine runs great in park and in neutral position. Once selected in Reverse or Neutral with the brake pedal pressed, the engine will stall, it seem like the torque converter is engaged. Tried reving the engine to about 2000 rpm in park and shifting into drive, the engine stalled and tranmission made a clunk noise.

Took off the tranmission pan, very little sediment in pan, transmission fluid was a bit discolored. Replaced the TCC switch on valve body of tranmission and valve body gaskets. Replaced Transmission Torque Converter.

No change in the Automatic Transmission and is still stalling when shifted into Drive or Reverse.

 

I asked in the other thread regarding this, but if you put it in gear without the brake engaged, will the truck roll, or does is still stall out. Also, MrShorty (I think) mentioned that this can indicate a problem in the valve body. That would make sense, because an incorrect routing of the fluid would cause the torque converter to lock up. Reason I ask about the behavior without braking, is I'm wondering if other internals could be locked up.

 

With the brake disengaged, the engine stalls. With the brake engaged the engine stalls. It like the transmission is alway engaged.

 

Those can be pretty classic symptoms of a stuck torque converter lockup clutch. If you pick the drive wheels off the ground (so there's essentially no resistance), does it still stall (be carefull don't get hurt)? Usually this sort of thing is a problem in the valve body, but it can also be a problem in the torque converter.

 

Yours might be different, but the wiring diagram for my 95 Taurus shows that the PCM grounds the pink/yellow wire from the torque convertor clutch solenoid to lock the convertor.

If you have a wiring diagram find the same wire & check that it isnt grounded out.

Have you pulled the codes? You might get a code 627 "Convertor clutch solenoid circuit failure."

 

I will need to check into this, will get back with you on what's happening.

 

According to the diagram at the autozone site, the '94 Ex TCC solenoid has a purple/yellow wire from PCM terminal 53 to a common red wire back to PCM terminal 37. There also appears to be a diode in parallel with the solenoid. I don't know what would happen if the diode fails (but I wouldn't think that a diode would fail very often).

 

I will check to see if the purple / yellow wire is grounded.

I will also lift rear vehicle, then start vehicle and shift to drive, will check if it stalls or keeps running.

Will keep you informed on what's happening.

 

Lifted the four wheels on a lift. Started engine. Depressed the brake pedal, shift into neutral release brake pedal and shifted into Drive, and the engine stalled.

 

Getting back, The problem was in the valve body, and was fixed.

 

Precisely why I prefer manual transmissions.

 

I have a 92 X(A4LD)and have the same problem but when I lifted the rear wheels with brake pedal pressed the engine stalls, but when I dont touch the pedal it works fine.... I noticed that the booster was hissing(Leaking) from the vaccum tube round seal coming out... I will change the seal tomarrow but it doesn't seem to be that simple.... Should I also change the modulator? Any Suggestions??
History of x. Stopping at a red light and engine died. Starts up but when put in gear engine stalls. P & N fine R,OD,D,2 & 1 all kill the motor. Wow I am glad I found this site. I already bought a used trans but I was reading the posts and decided to do some checks first.
Any help would be greatly appreciated!!
Steve

 

A vacuum leak will stall an engine. Good idea of fixing vacuum leak first.