2001 Land rover discovery with 155k Miles. plugs and wires done 20k-25k Miles ago
Car was misfiring so we took it to a mechanic. Diagnosed that cylinder 1 and 6 were the cause so they determined that the coil pack crapped out. We replaced both Coil packs and that seemed to solve the misfires until now(this was less than 500Miles ago). At idle the car is completely smooth running perfect but under half throttle acceleration car starts to misfire. SES light never starts flashing. ultragauge shows pending codes:
p0300
p0301
I cleared the codes hoping they would not come back. They did not come back
This was about 2-3 days ago.
Today i start to drive the disco and it was running very well until i had to accelerate at about half throttle. The disco was misfiring but still no SES. I let off the trottle a bit to about 25% and A couple of seconds later The ultragauge beeped saying there was the following pending codes:
p0300
P0306
Thanks

 

Suggest you install a new set of platinum spark plugs with the proper .040 gap now that you have new coil packs.