The engine in my 4 litre X300 has a little misfire when it is in drive while stationary waiting at the trafic lights but only when the car is at running temp and has been driven for a while.
While this misfire is not violent it is a annoying and it does'nt seem to register as a fault code on the onboard computer.
I have been advised to replace the coil packs.
Any other sugestions would be greatly appreciated.

 

I would not run out and spend over $600 on coils! Check to see if you have oil in the tubes. The spark plug boss seals will leak and cause this problem. Also, inspect the boots for cracking. You may be arching in to an oil leak or through cracked boots to the valve cover.

Always inspect before spending!

 

Hi Ken
We found the fault and it was a Coil pack, there didn't appear to be any oil in the chambers and I had the front 3 coil packs replaced under a mechanical insurance and this didn't work so I got the old coil packs and repaced the rear 3 with the old front three and there was no more problem
Thanks for your help

Cheers Derek

 

Hi,

I have very similar problem. So far I changed the spark plugs, no improvement. Is there a way to check the coils? Something like measuring the resistance ?