i went out the other night and had a go at my 7 after about 20-30 mins of driving hard, i suddenly felt the idle was rough

i was heading back home on 60-70kmph normal cruising speed the car was running fine but i could tell that there was some problem with the plugs or ignition and just about there i up shifted and a huge burst of fire came out the exhaust. i had tried changing the plugs the next morning 2 plugs from the front rotor where half wet and i assume they were to able to burn the gas... the rear plugs seemed fine..


could this be a ignition coil problem... ???? so do you guys suggest its something else...

i had removed the UIM last night and will try to test the ignition coils today... i just hope its not the rotor it self... and i dont think it could be, my new engine has only done 7-10k KMS and on the dyno with only knightsports highflow cat it ran at 263.9 whp...

 

Compression test it first. Hate to say it but if only the front plugs were wet and theidle was rough it doesn't look good. Mileage on an engine means nothing, what vacuum is the car pulling while idling and at what rpm?

 

the car idles at 500 rpm now and vac is -23 on the blitz turbo timer, when the car was fine it used to be -40 at 700~750 rpm, well it still is only if i hold down the throttle to 700...

i drove it after this problem without boosting, and while driving there seems to be no problem....