derick_hoda

Lately I've had several problems with my 2002 Jeep Grand Cherokee Limited (4.7). Three codes in particular have been showing up: 1. System too lean 2. Torque converter clutch solenoid circuit 3. Evap emissions leak/ no flow. My jeep was running terrible and wanting to die off when I tried starting it. Luckily changing the fuel pump solved that problem (eliminating the "too lean" code) but not the evap emissions. Also I cannot find the torque converter clutch solenoid. Any help would be greatly appreciated, thanks.

dave1123

The torque converter clutch solenoid is inside the transmission pan. I have the same code P0740 set on my WJ and the converter is showing a failure to lock up. After all the research I've done there could be 3 reasons for this, failure of the solenoid, debris in the valve ports controlled by this solenoid, or failure of the torque converter clutch itself. Of course, all the shops I've talked to tell me to rebuild the transmission. Not going to happen until I've exhausted all other possibilities. I've gotten it to pass inspection by clearing the code and driving it about 50 miles with the O/D off before going for the inspection. It's costing me about 2 mpg with it not working.

The only difference the lock up converter makes is about 200 rpm at any speed and no rpm change between power and coast.

The evap code is probably your canister purge solenoid. If it's working, you should hear a cycling click (on and off) on cold start-up while the engine warms up. This is the solenoid clearing the canister of accumulated fuel vapor trapped and condensed on your previous run. Another thing it could be is a vacuum leak or vent line leak in this system.

Welcome to CF and the world of the jeep sickness.