Alright everyone, i know there has been some debate as to whether stock NGK platniums or Denso iridiums are the way to go. So today i am going to install 6 denso's into my 2001 a6, 2.7t. i believe i currently have NGK platniiums i will confirm as soon as i pull the first plug. I do mainly highway driving, about 500 miles a week averaging 21.3 calculated and computer 21.4 mpgs. i also have an apr stage one 93 octane chp so i'm cranking out around 315hp. once i run a couple tansk through i will repost here and let everyone know the results.

 

well the plugs are in. did a K&N airfilter while i had the plascitc off the engine. i'm still on the fence about the plugs. they run great no skips or misfires at low throttle, but after half throttle i get sputter and skip and the check engine light blinks, saying i could damage the cat? right now it has a solid check engine light, hoping it just a timing issue, having it scanned tomorow. has anyoen had similar issues? only put 50 miles on the plugs and am writing to denso to see what they have to say

 

This could be a good thread...Keep us informed on what the issues are. Try puting in the original plugs and see if anything changes

 

so i had the code pulled today for the car. misfire in cylinder 1. i ordered pfr6q's from my mechanic so i'll be switching back to those. apr, my chip manufacturer, had little to no advice as to why t would mis fire at high throttle/boost situation. my mechanic and i can olny guess the plug is running to cool or to hot. i'll be pulling them all out tomorow so if anything looks suspect i'll post some pictures. to bad these plugs dont work they run great at low boost situations/ like cruising the highway/ got an extra 2 mpg's even in safe mode. i'm also going to be doing some searchign via the net to find some temp ranges for where ngk pfr6q's run vs denso ik20's. maybe it would be a sinple switch? who knows. only time will tell

 

i'd liek to add the denso's came pre-gapped at .04 inches, whiel the ngk's i removed were still around the .032 inch mark. maybe i will regap the iridium to .032 or maybe smaller to decrease plug fouling seeing as my chip dumps more fuel in at full throttle/boost situations. which is where i'm having the issue. thoughts?

 

ok, so today i have re-gapped the plugs from .04 down to .03 inches. car ran much better all around. misfires were few and mostly 6th gear full throttle/boost. goign to close the gap a little more tomorow after work to .025 inches. to be the best of my assumptions because i stil;l don't understand the heat range of spark plugs as well as i would like, i assume the spark is being blown out by the cylinder pressure. turbo's and how they chaneg the performance of spark and cylinder performance is abotu 3 months new to me so anyoen who has some experience with this i would be glad to ehar from you. also mod, anyopne you can suggest would be good to hear about.