03 Termi MISFIRE

[smmachnik]

Hey all,

I do not have much to go on here. Looking at making a possible purchase with limited mechanical knowledge. Being a mechanic his whole life my father usually helps me on this but im turning to you guys to see if anyone has seen this problem before. 2003 Termi 83k miles, seller(not on here) states: "Has a misfire at wide open throttle above 5k rpm sometimes. It seems to be tune related or fuel related. I stopped driving it til it gets resolved. Possible bad fuel rail pressure sensor (which i have and will come with the car)."

Only stated mods are as follows:
-2.76 upper pulley
-CAI
-billet idler pulley
[FONT=&quot]
[/FONT]Question 1: Can a misfire only at high rpm's and wide open throttle signal possible engine failure or anything that would require a full rebuild? (besides plugs, gapping, fuel, sensors, etc). Poor compression? (I'm guessing no or there would be problems throughout lower rpm's)

Question 2: Has anybody had a similar problem?

My main goal here which might be unrealistic: I am okay with dropping a few hundred here and there for plugs, sensors, fuel system, etc. I am trying to NOT replace the whole engine. I know this doesn't give you guys a whole lot to go on and I apologize for being a novice but any tips or info is appreciated!

 

[hotcobra03]

Welcome..cant answer much on tuning .but it appears than alot of guys have had issues after modding..

there are bad install issues..things missed.wired wrong

down to not doing all steps to support mods..


I can say as a daily driver..we have more miles than we ever expected.

my plugs now have almost 200k..most of car is original. .


you on a good start with asking before buying...

doing a basic compression/ leakdown test is always 1st step for me with any engine issue..

ive had a few head issues and misfire..overheating..all problems found with test..


visit stickys above threads..before you post read..

anything you want to know about this car is in that thread..

to help school you on what your car might have that past owner might not be aware of..


this site is the best but is slowing..just give some time on replies. .many will respond

 

[01yellercobra]

Miss fire under boost doesn't mean the engine is about to grenade. But getting a compression and leak down test down couldn't hurt.

For me a miss fire under boost was usually spark related. The COP's got week and needed to be replaced. It could also be the spark plug gap is too wide.

 

[SVTdreamin04]

Leak down and compression test for sure! My car had misfire issues on the Dino which was related to spark plug gap being too large. My car has a ported bower with a 2.76 pulley. I gapped my plugs to .032 and problem solved, well at least until I shredded a cam chain tensioner a month ago clogging the oil pickup tube.

Moral to this story is I bought my car a year ago and I could tell it had been beat on but most of them by now have been. I done my research as well but if you're mechanically inclined don't let minor issues hold you back from buying one of these cars. There are just some things you can't find until like a year later when they decide to show their ugly face on their own.