Well, after replacing the wires with Magnecores and resetting all the OBD2 codes, I am getting the same codes:

P0300
P0307

Also, the fumes keep getting worse.

Any suggestions?

This has to be an electrical problem! How do I troubleshoot?

 

Last question before spending thousands at the dealer before I get rid of it:

Couldthis misfiring be related to an electrical problem somewhere else in the vehicle (i.e. lights, windows, HVAC)?

Thank you all for your responses.

 

I got the same problem, my check engine light flashes but not constantly.
Smells terrible! I got about the same readings and to top that up the back sunroof window broke on me (SE7 if that matters), well that's not really all.
I put a new exhaust system, the old one sounded like a broke racing car.
It starts but it won't go over 10mph and misfires, it sounds like is going to explote.
When I open the gas cap to put gas in it sounds zzzzz like is running on fumes but is really not (I don't know if this matters)

Anyway, this is my first Disco and I don't want it to be the last one. Is GREAT! when it works.

Any thoughts?

 

I had misfiring also before I had done the heads at 106K miles (10k ago) and on Mike's recommendation I had replaced all four O2 sensors. New wires were also part of the repair. The engine runs now smoother and stronger that itdid at 50K, which I could also attribute to professional valve job and head resufacing, which has increased the compression ratio. Bottom line is, O2 sensors are important element of yourengine management systems and it is vital to keep them in good order.[sm=smiley16.gif]