ok so i bought my car about a month ago and have been driving it a little over 2 weeks. ive noticed that if im at an easy ride and hit the gas then it seems to misfire and jump then takes off after a little jerk. i raced a buddy of mine and as im taching up, the car starts jerking and jumping then after about 7k it does it bad. whats the deal with this?? ive already replaced the plugs and that helped none. it only seems to be getting worse. wires are coming in next week. whats going on?!?!?!?!?!?!

 

The problem is your street racing.

 

nah. the track isnt the street

 

Any check engine light?
If it gets worse as you're getting up in rpm, that's not a good sign... when were the standard bits, coilpacks, wires, last replaced? Was the cat replaced at any point? Does the cat glow after pushing the car?

 

You didn't say you were on the track. My bad. I assumed when I shouldn't have.

What kind of maintenance have you done to the car? How many miles on the car?

Sounds like it's time for coils, plugs, wires, MAF cleaning, air filter, oil change.
Perhaps a new Catalytic converter.

 

ok i do have a check engine light. its for a small vacuum leak. the tire pressure light is also on. i had a highflow cat put on because the other cat was deleted. i havent checked it but i can next time. that was put on about two weeks ago. the plugs were changed last friday and the wires will be changed next week. im not sure if the coils have ever been replaced nor anything else.

 

Does the check engine light flash when this issue occurs?

 

your good. i changed the oil exactly 1043 miles ago. new cat and 2 and a half header back exhaust with single chamber flow. but it was doin this before the exhaust was put on. including to cat.

 

oh and 70000 miles or so. on an 04.

 

Coils, coils, coils

 

no engine light flashing either.

 

yeah thats what ive been thinking too. FML!!!!

 

yes its on the whole time.

 

Get new coils. And you have a custom header on the car? Is that what I'm hearing?

 

Fix the vacuum leak.

 

sorry exhaust manifold. shoulda made that clear too. the guy that plugged my car said the vacuum leak is just from the gas cap. could this be true?

 

yes. who made the header?

 

its a manifold again... my bad.

 

good advise

 

Okay, let's recap.

Plugs changed, wires on the way.
Hi-flow was put in less than two weeks ago.
No proof that coils have ever been changed and you have 70k miles.
CEL supposedly thrown by gas cap....which that EVAP code(P0420) and probably is the cap, BUT you need to take care of that so you can see if the code goes way or not. If not, then it might be a real vacuum leak.

I would think at this point you gotta get those coils out of there.

But......a vacuum leak other than the gas cap could also act like this. Have you check the entire intake track and made sure that there are no leaks? BTW......you might want to clean the MAF sensor as well.

 

could it be a bad cat although i just got a brand new highflow installed?


oh btw. intake is a clear passage. k&n drop in and i cleaned the tb and the acordion tube with seafoam and a water hose, then dried it all good.

 

Did you break or crack one of the plastic elbows on the accordion when you took hoses loose to take the accordion out, or did you just leave it on during this cleaning?


Are the screen(s) still in the proper places in the intake track and haven't been removed, knocked out of place, or mangled?

 

well of course i didnt spray water in the tb. just lettin yall know.

 

not that i know of. im not sure of what youre talking about...

 

ahhh. the oil elbows? not that i know of. i could check though.