Friends 986 threw that code. We cleaned airbox and filter is new, reset and code is gone. No warning lights or codes. Driving home after driving for a couple minutes, he said he had it pegged but the car only reached 3k. I told him to stop and try again and it revved like it was suppose to? Any thoughts on where to start. Oil and fuel caps are tight, airbox is clean.
MAF/TB cleaning? Other?
Thanks for any advice.