Part throttle surge

[wjurls]

Recently my 03" Cobra has started surging a little only under a part throttle (Just barely tipped in cruise) condition and only occasionally. Almost feels like the timing is fluctuating. I have recently put a time-sert bushing in #7 and replaced the clutch with a Centerforce DF and an MRT catted H and Magnaflow CB. No other changes have been made since my tune. I have never noticed the issue at heavier throttle positions. Any clues where to start looking?

 

[EvanStang]

what kind of spark plugs are you using?

 

[wjurls]

Autolite Iridium XP gapped at 35. They have been in place since pre-tune.

 

[snkepit]

Need ngk's

 

[wjurls]

C'mon now, NGK's aren't the only functional plug in town. Even my tuner says that the Autolites are just fine and the same temp as the NGK tr6's. Not to mention these plugs have been in the car for a while and even recently inspected and this issue has never surfaced. Any other idea's?

 

[wjurls]

Just an update for anyone that finds this thread in a search. I went and looked a little closer and noticed that my FIPK fliter had come off the intake and was just sitting there. The way it sat there you couldn't really tell that it was off without looking at it specifically. No more surging problem.

 

[Mystic03]

dumb question but what is surging?

 

[wjurls]

It is subject to interpretaion but in my case, while I was giving it gas, it would seem like the power was real inconsistant and it would kind of feel a little like on again off again turbo lag. Didn't feel like it was missing at all but just a sloppy acceleration.