We've had this XJR with 117k miles for a bit over a month now and when I jam on the accelerator hard from a 5mph roll it goes well thru first, second, third but then grabs and releases fourth, like a missed shift on manual transmission . DSC is on and no wheel spin as I would expect with it on. I back off throttle, DSC flash a couple times and I can re-engage with a small amount of throttle. Does in both regular and sport shift settings. Only error code I get sporadically is 'air suspension fault'. Trans was serviced by Jag dealer around 60k according to Carfax. Any ideas??

thanks

Bil

 

If the dsc flashes I would check the tires they could be too old, hard and slippery. White at it replace the spark plugs and coils as this can also cause this issue on shifting; very little misfire can confuse the transmission.

 

Ok so the transmission was "serviced" around 60k did that include a oil/fluid change? If it was a Jaguar dealer I suspect not.

If fluid is original it is way overdue for a flush.

 

Yes, just says 'transmission serviced' by a non Jaguar Dealer. I'll get it changed and replace plugs as there seems to be an almost undetectable misfire during heavy acceleration, no codes or pending codes. Replaced coil packs about 2 weeks ago.

Thanks
Bil