Greetings,

I am - and have been - searching the forum for my new problem, but thought I would also put it out here as a new thread, as it seems just about every issue with this car has already been discovered. I am hoping the collective can provide some places to start in running down this problem.

2005 XKR, just turned 70,000 miles. Yesterday on the way home I noticed the engine was idling a little bit rough, no codes thrown. At a stoplight it died, but started again without issue. When I got home - after really being light on the throttle - I gave it a few pumps on the gas to rev the engine. At about 3,000 RMP, it started missing really bad, so much vibration it felt like the engine was jumping around under the hood. Back to idle, only a slight roughness, and seemed to accelerate pretty smooth until hitting 3000-3200 RPM.

No sign of leaks anywhere, no codes (at least on the display).

Thoughts on where I should start first? Thank you.

 

The reason it seems to miss at 3000 rpm in park or neutral is because you're hitting the rev limiter. It is there to stop you over revving the engine and is disabled when in a drive gear.

Start looking for air leaks on the hoses but you may need jag diagnostics to pinpoint the problem.

 

Thanks, I feel kind of sheepish now, I should have known that....

 

No problems, it felt like that the first time I did it.

 

You could try a hard rest (remove neg battery cable and touch it to pos post for 15 secs then reconnect neg cable)

This will reset the ecm idle parms and the car will relearn them, if you then have the problem of it dying at a stop we'll need more investigation.