Hello everyone,
I have a 2013 Jaguar XF 3.0L awd supercharged with cold air intake, stage 2 tune, upgraded crank pulley, and muffler delete. Anyways I recently blew my supercharger so had a used one from a xf that at 32k miles on it put in my car. I also had my spark plugs replaced once I got the car back I started to notice a issue. The car runs fine until you try and floor it then it starts to miss fire but no engine light and no shops computers can detect a missfire in the cylinder. It only does it under load. The original shop said o ur used supercharger is bad but I experienced a bad supercharger with my last one and this wasn’t the issue. Other stops claim that my mods are causing it which I don’t believe because it didn’t happen with my other supercharger. No one seems to know what’s wrong. I had a smoke test done to see if maybe the supercharger and intake manifold would on completely but it came back with no issues with that. I even checked all the hoses sprayed them all to see if there was a changed in rmp for a vacuum leak. That resulted in me not finding anything. I have noticed my rpms do shutter but only slightly when I had my car dynoed they noticed pulsing in the results you can see little breaks in the lines in the dyno. Some days the miss fire feel like they are not there then other days they are worse. Jaguar won’t look at it because it’s modified and no shops seems to have any solutions. Do you guys have any idea what could be wrong, please help

 

Hi,
This forum is for the X260 (2015 onwards) model.

Your XF is the X250 version for which there's a separate forum on this site, you may find some help in there.
Cheers
Nick