While on the way to LAX last week, my D2 threw P0300/P0308, I cleared the code and parked in her in the lot... Get back from trip, drive a few miles and P0308 is back. I have pulled plug 8, no oil nor fouled, swapped with plug 6, still misfires on #8. swapped plug wires, fault follows the wire swapped. There is no coolant loss, so I ruled out crack in the block, head gasket was done within the past 18 months (no issues there) and the fault doesn't go away when the rover is warm, although I can clear it via UltraGauge and it might not be present for 2 hours or more. I purchased my Magnecor wires from UltraRev this past August, and in that time I am almost at 5K miles driven on them. I have called UltraRev during business hours and no one answers, I have emailed and the email is returned as undeliverable. It appears I am needing just a replacement #8 wire, does anyone know if I can just get wire #8 if UltraRev drops the ball? Should I buy a cheap wire set and just use the wire for cylinder 8 in the meantime and if I go that route, will it mess anything up?

If I am unable to resolve with UltraRev, will try reaching out to Magencor directly.

 

Try getting just one expensive spark plug and replace it. Then see if it works. Usually it does.