Yesterday I was approaching the freeway and had to fully accelerate in order to avoid an oncoming vehicle. The XK downshifted into “passing gear” and after I noticed that the engine RPM was somewhat erratic. Specifically, the RPM was indexing, for a brief period, before it settled down.

Anyone out there had this experience?

 

Dave - what is the elevation where you have yo' crib?

 

3 thoughts in no particular order. Rev. limiter, MAF or Oxygen sensors. If as you state, you had 1 down shift while merging, rev. limiter not likely but I would definitely check out the other two. If they all check out you may want to look at the fuel filter.

You did not state the milage on your car.

 

Thanks for the replies, the elevation 700 feet above sea level and the mileage on clock is 32500.

I will drive the car this weekend and try to duplicate the symptom.

 

So your elevation should not be an issue. At higher elevations the oxygen and pressure levels are different and requires adjustments for ignition - sometimes these corrections are sluggish - that was my line of thinking. I thought since you were in Nevada you may be at a high elevation.

 

One of the many symptoms I experienced on my 08 XK attributed to a failing battery was erratic RPM's from time to time. A new battery cure all of my electrical gremlins.

You can get the battery checked from free.

Good luck

Tom