The automotive world has known how rugged and durable Jeeps are since they first hit the consumer marketplace. In the 1990s, however, the world of SUVs took a turn for the luxurious, and Jeep fell behind. In 1993, Jeep released the Grand Cherokee in an attempt to catch up with the times. The 2002 Grand Cherokee came standard with a 4.0-liter, in-line six-cylinder engine that produced 195 horsepower. It also had an optional 4.7-liter V-8 that cranked out between 235 and 265 horsepower, depending on options. The throttle position sensor connects to the throttle body on the engine and sends pertinent information back to the vehicle's computer system. Replacing the TPS in either engine for the 2002 Grand Cherokee is relatively easy.
Trace the air intake tube -- the plastic tube connecting the air box to the engine -- toward the engine until you locate where it connects to the engine, this connection point is the throttle body. Loosen the hose clamp holding the hose to the throttle body with a Phillips screwdriver and pull the intake hose from the throttle body.
Disconnect the wiring harness plugging into the throttle position sensor -- the electrical component on the driver's side of the throttle body -- by pulling up on the locking tab and pulling the harness from the TPS.
Remove the two retaining bolts from the TPS and pull it from the throttle body. Notice a shaft protrudes from the side of the throttle body and into the TPS.
Set the new TPS so the shaft on the throttle body inserts inside the TPS and rests against the tabs inside the TPS. Rotate the TPS a few degrees to line up the bolt holes in the TPS with those in the throttle body and hand-tighten the retaining bolts. If the TPS will not rotate to line up the holes, remove the TPS and install it so the throttle body shaft is on the other side of the tabs inside the TPS.
Torque the TPS bolts to 5 to 6 foot-pounds with a torque wrench and socket. Plug the wiring harness back into the TPS and listen for it to click into place.
Reinstall the intake air tube on the throttle body and tighten the hose clamp with a Phillips screwdriver.
