Originally Posted by Jonny954
I had been running the v301 maps (stage 2 aggressive) since I bought my cobb a few months ago, no problems whatsoever.
When v401 maps were released I of course upgraded and ran those. Within a few minutes I was getting misfires, for the first time.
So I went back to v301, same thing but less. Stock map was fine.
Changed the 1 coil (cyl 1) and have been running v301 for the last 3 months again without issues.
The other day I thought I'll give v401 another try and the same thing! (cyl 6)
Can s.o. please elaborate why v401 is making my misfires appear...?
I'm at 54k, downpipes, dci, PE exhaust...
As enrita said, your sparks plugs may need to be changed. Most change after 20k miles on tuned cars.