My 1996 XJ6 vanden plas ,the engine skips sometimes more frequently . At worst it has a little hiccup every minute or so wether cold or warm.

 

First thing is to remove the exhaust shield and check for cracks, next is coils and spark plugs - there might also be some oil-seepage in the plug wells causing shorts.

 

Unless you have replaced it recently, I would add a crank position sensor to the list. Amazing how frequently it turns out to be the culprit on X300 faults despite rational thought suggesting otherwise!

 

Not sure I follow? What does a skip, or hiccup mean. A dip in the RPMs?

 

maybe a single miss fire is a more descriptive term

 

thanks for that response

 

ok thanks

 

When was the last time the coils were replaced?

Cold engine would seem to discount most of the sensors failing, since most of them are not being read for fueling until the engine is warm and it goes into open loop.

 

My car had this. I removed each coil in turn and listened very carefully. Each of the cylinders caused the engine to run rough of course but I could also detect the occasional misfire on top of the rough running. When I disconnected cylinder 5 the misfire wasn’t there.

I replaced coil 5 and it was fixed!

 

Or you can just order a set of six QYL branded coils, which forum members here have had very good experiences with, and swap them all out!