My xj8 is occasionally applying throttle to the point where I have to hold the brake to keep from running into things at low speed. I got one engine failsafe mode message once and it went away as soon as I turned the engine off and then on again. I'm not getting any codes besides p1637 and p1000 which don't seem to be related. At this point I don't find the car safe to let anyone else drive who is not prepared to stand on the brake. Anyone else experience this? Any thoughts are appreciated.

 

possessed jag, very common problem, i'm not sure what the PXXX code is for that.

Sorry, no idea here. But please put the year and engine size so others might help you. Could vary year to year.

 

This happened to me once. When I restarted the car, it went away. Try cleaning the MAF sensor. Mine was very dirty when it kept applying the throttle