I have an idle issue that just started…after replacing my battery, my idle seems to running about 650 rpm’s…about 75 rpm’s more than normal. To add to that issue, now the transmission “hard shifts” Into first gear when coming to a stop.

here is the most recent maintenance history..
At 98k miles plugs, coils, atf, oil/filter and air filter changed….no idle issues
At 101k miles thermostat, housing and water pump changed….no idle issues.
103k miles headlights and new agm battery installed. This is when it all started!

As the temp has been dropping to 50 degrees in the early mornings, the start up seems fine and the idle works it way down to 650 ish. There is a heavy smell of fuel coming from the exhaust on start up from cold only.

I did disconnect the new battery to reset everything since everything jag seems to start there!

Any thoughts on where to start to resolve this problem?

Thanks for your input!

2007 Jaguar XK Convertible

 

IIRC, it takes some driving for the computers to relearn your driving habits. Sorry thats all I got.

 

Forgot to mention that I drove the car about 75+ miles after installing the battery and about 50 after disconnecting it.

thanks - john

 

I wouldn't say you've an idle issue. Could be your fuel adaptations reset with new battery. Takes a couple of hundred consistent miles to reset or you can use the factory software, SDD to do a reset.

 

Thank you both…I guess I need to be a bit more patient! Not a strong suit of mine.

 

Battery off resets fuel trims and all OBD monitors.

Give it a while to relearn - or better yet use OBD to check the monitors set (shows all is OK and various legalities demand them set) and watch the trims to see if all is OK or you have a fault you maybe don't yet know about.