My 01 XKR was running perfectly until a major rainstorm when it started to feel like it was misfiring.

It did not show any codes. I decided to replace the spark plugs with eight new NGK Ruthenium plugs and four new NGK coils to replace the original Denso coils. There was no oil or coolant in the spark plug seats when I checked before pulling them.

It really did not make any difference, it seems to idle fine out of gear, but put it in drive and it stutters.

Still no codes. I cleaned MAFS and the part load breather. Still the same.

It has dried out for a month now and I am at a loss what to try next.



Thanks,

Karl

 

Which of P1000 & P1111 do you have?

Note: do not clear codes or disconnect battery as you will cause P1000 and then most code cannot flag.

 

Why only 4 coils? My 4.0 S Type had random misfires for a long time with no codes until I finally replaced all coils and all was good.

 

I have 2 new 4 pin coils if interested, one Denso, other unknown. Both new.

 

Apologies for the late response, I just finished setting up my new computer and had to reset my login.
I replaced the remaining 4 coil over the last 4 to 5 years. Just to be safe I ordered 4 new NGK coils. They should arrive later today.

Thanks for the advise Jag V8 and Rex. I will post what happens after installing the new coils tomorrow.

Regards,
Karl