I have a stock 04 WRX Sedan that has about 1,650 miles on it. I have had it for about two months, and I have noticed three times that it has hesitated when being run at around 4,500 - 6,000 RPMS. Mostly in third gear if I recall... It feels like there is a total loss of power or lack of fuel, but as quickly as it looses power it picks up again. The car kind of bucks when it does it. Every other time, the car runs great. I am wondering if it has to do with the ECU getting goofy readings. I know there are alot of people that have done grounding mods to improve the smoothness of their WRX, and I also wondering if that might help. I always run good 93 or 94 premium fuel so I am pretty sure it is not that. Any one else had a similar problem?

Thanks!
Rock

 

hmm, it sounds like the factory ECU is detecting knock. You're using at least 91 octane fuel, right? I'd take it in to the dealer and get it looked at, and tell em it's knocking.

<edit> never mind i see you're running on 93, get that thing checked out by the dealer!</edit>

 

Yes, I am using 93 and higher. Does the factory ECU "log" knock detection? Would they be able to pull a code?

Thanks for your reply platypus!