Good day guys! Just picked up my 2009 XF supercharged 2 weeks ago. I bought it from a Jag dealer so it went through their used car inspection and they addressed a few issues with it. I also talked them into a 1 year warranty on the car for anything that may come up. Problem I seem to be having is when the car starts it feels like it is missing for a while RPM is about 1200 then slowly drops to about 700. I know the ECU needs time to adjust and from my understanding the O2 sensors need to heat up and once they get to temp the car will go into close loop mode. Anyhow not sure if other guys have this rough idle on start up?

Thoughts would be great guys Thanks

Brett

 

Regarding your rough idle, if you have not checked your air filter- make sure its clean.

 

They are known for having air leaks on the back of the supercharger/intake due to a crack in a rubber/plastic tube. It's possible there is a slight air leak. I haven't seen it in person so I can't give you a exact description. One of the techs on here (Brutal) commented about it a while ago. He said he fixes them all the time. You'd think you'd get a check engine light if there was a leak but it may not be bad enough yet.

Edit: Found his post: https://www.jaguarforums.com/forum/x...22/#post449762

Run a search on "idle" in the XF forum. You may get a few more ideas that you could look into.