Hi all,

I have a 1998 XJR. I have been having a problem with how it runs at WOT (now with flooring it when I'm at high speed, approximately 50mph). It's a hesitation and skipping in rpm. I had that hesitation pretty bad recently throughout low gears to high, but I've kind of fixed it by changing the gap of the new spark plugs. Believe it or not, it helped. It used to do hesitate from low end launch from a stand still, but that went away once I re-gapped the plugs to .045 or .044 from .050 (ngk). Now it only does it at WOT from high speed at approximately 50-60mph. Can the wheel speed sensor have such effect on the car to make it fell like it is hesitating to climb in rpm/speed? I have the car off traction control while performing this (have not tried it with traction control on). And while with it off, it doesn't burn rubber with one foot on brake and the other pushing gas. Can a faulty wheel speed sensor affect such performance? Thanks much.

 

From your description I don't think your problem has anything to do with a wheel sensor. If you had a bad wheel sensor you would have the ABS light on and/or a 'traction control not available' message.


Sounds like it may be a bad secondary fuel pump