Guys, I have read the post on the forum on this issue. Need your help. '99 xk8 with 141,000 miles. Car started running rough, acting fuel starved, then it goes to "engine fail safe mode", "limp home", "stability control failure". I can restart and all is fine for a few minutes. Rev motor and they return. I have a strong smell of gas but no leaks. I have cleaned the MAS air sensor, replaced a vacuum line, can't find any more leaks. Any ideas? Battery is 13 mo old.
Thanks!
LaRue

 

That happened to me a month ago while in Dallas bumper-to-bumper rush hour far left lane. Limped to a Jag repair shop. Turns out it was Throttle Position Sensor which according to them isn't sold separately. He had an extra Jag throttle body that he canned the sensor from and put on mine. Also the intake bellows was cracked so he got one from dealer. Then checked out the cat. Whole thing was $400 or so. I wound up having to spend the night because it happened the night prior. I feel blessed because a throttle body is $2200. Yes, I feel blessed. Let us know if there is an alternative to buying a whole throttle body. Good luck.

 

resolved: I hope! I cleaned the throttle body after I heard it "rattle" sounded like an octane knock but I could see the throttle plate vibrate back and forth looking to seat. I did a quick clean and it seems to be OK now. Thanks for looking!