My XJR is dealing with a weird issue.... I can feel the car jerk when it shift gears in 1st and 2nd.... and it gets slightly worse for a week... then the Restricted performance light comes on, and it disappears almost immediately. The check engine light stays on for 2-3 days and goes away... and the process repeats every 2 weeks.

What do you think it is? Vacuum leak? Injectors?

 

Have you plugged an OBD in? it'd be good to know what codes are thrown before we start guessing.

 

I get codes that its running rich. Thats it. Then it clears itself up.

 

As a first move, you could check that your transmission fluid is at the right level.

Then you could look at doing a transmission adaption procedure. There is a pdf around here that details the procedure.

 

Transmission fluid level could trigger Restricted performance with codes that are saying its running rich?

 

P0172 and P0175, running rich on both banks

 

Cleaned the MAF sensor?

 

cleaned it, is only a year old, pinched in the pins to make a better connection.... still same...