I have a really bad hesitiation around 4000rpm and up. The car doesn't gain any power at all when the hesitiation starts. I have tested out the tps sensor and everything checked out good. I have swapped out plugs and the coils. All of my grounds are new wire (2g). The compression test showed 90 across the board. Any other ideas or test i can try? My 24hp murry mower is faster than my car right now.

 

it might be the clutch. i had the same problem last week and my cousin told me that its definitely my clutch. so i went to go buy a ACT n/a clutch kit...kinda expensive. ~$400

 

well i ordered a new clutch so when that gets here i will put that in and put my lsd rearend in and all royal purple oils in it and see if that gets me anyplace. But i dont really think its the clutch b.c when a clutch is slipping it normaly revs fast. my problem seems more to be it jerking from like 5k got 5500k. Any other ideas?

 

did you check your ports i think after a certain rpm your ports open up and that kinda sounds like my car.

 

Check plugs and wires. could also be stuck auxilary ports.

 

bump anymore info would help? plugs and wires are good. auxilary ports aren't stuck

 

I have the same problem at the 5500k mark. I have posted a few times with this problem but keep gettin nothing. Good luck.

 

How old is the fuel filter?

There are grounding issues that can cause hesitations in that range but I don't think it would be that bad.

You're sure it's not the auxiliary ports actuation?

 

Thinking the same thing. It might be starving for fuel at higher rpm if the filter is clogged up.

 

When you checked the TPS did you look at the sweep in values as you worked the plunger in & out?
The Idle setting can be perfect, but if the signal sweep has a bad spot as you open the throttle, the ECU will freak & give bad misfires.

 

I'm going through the same thing right now. This weekend I will put in a brand new fuel filter and clean my grounds. My TPS and Aux Ports are working fine. My plugs are new, but the wires are old. Once I get the problem fixed, I will post it up so anyone else who runs into this issue will have something to go by. Good luck!

 

Im going to pretty much take it down to a short block and redo everything. The main spot is right at 5-5500rpm. my ports are wired open. fuel filter is only a couple months old, fuel strainer is only a month old. injecters were rebuilt a year ago. Clutch should be here early next week I am going to put that in i know mine is going bad. Thanks for the help keep it comeing i will keep yall up to date.