My friends FD has an odd problem. When he hits 5,500 the car hesitates really bad. Like runs great all the way up to that point and just stops it seems like a rev limiter. If he pumps the gas at that point it slowly goes up past 5,500. Its wierd as hell. I rode with him to pick up my FD from the shop and when he first starts the car it runs all the way up to redline. once its warmed up thoe it laggs out again.

WTF!? lol

 

What mods are on his car?

 

stock

 

I would start by:

1. Check/change the spark plugs
2. Check for engine codes
3. Check the double throttle

Those would give a good start at things to look at and evaluate.

 

Might be the Mafs. Happend to me. Would get to a point then lose power completly, Just changed my sensor and it worked.