I just got my comptech headers installed this weekend and now my car is idling rough. It is only when I am stopped and have the car in drive. Also, If I hold the brake and give it just a little gas the car vibrates and makes a vibrating noise when the rpm's are coming back down. I just got my car back from the dealership and they think It might be the headers. Please help me if you can. Thanks!

P.S. I have a 02 TLS If this helps.

 

Anybody?

 

Maybe headers need to be tightened, but I doubt a slight leak would make the car run that rough. How about a loose O2 sensor? Any dash lights come on? One thing you could try is to reset the ECU and see if that may help. If it's not the headers, it could be an engine mount.

 

When the car is running rough, can you hear any odd noises from the engine?

 

I checked the O2 sensor and no lights have turned on. I also have tried resetting the ECU with no luck. Whe the car is running rough the only thing I hear is the exaust shaking when the RPM's are coming down. It feels like I am driving an old car.

 

My car used to do the same thing only when the engine is cold and I have it in drive. When I took it to have the timing belt changed at 113k miles, I explained to my mechanic and he said he cleaned valves and it doesn't do it anymore. Also he advised me to be using fuel additives that clean out the fuel injector and stuff. You might want to try that

 

My car still does It when the engine is fully warmed up but I will try some Seafaom cleaner tonight. Hopefully It will help. Thanks

 

Mine does similar things.

When I'm coming to a stop, the car vibrates, and vibrates once more after stopping completely. At the same time, the RPM drops down to 300. The car is bogging.

Does this sound familiar to you? If so... join my club. I have no definite solution, but have come up with 3 possible causes --

1. Running too rich.
2. Primary O2 sensor dead (indeed, the heater circuit is dead and my CEL light is on)
3. IACV malfunction


Therefore, I have ordered a new O2 sensor, a V-AFC II unit to get the car tuned, and am cleaning out the IACV this week after my finals. If that doesn't fix the problem... then my headers are coming off (OBX SS).

This isn't good news to me, since I was planning on ditching the OBX SS headers and going with Comptech.


Anyway... in my car, it's a lot worse when the engine is fully warmed up. It doesn't do it, or at least not as badly, when the engine is below normal operating temperature, which leads me to believe that it is indeed running rich at op. temp. I'm also getting Mugen T-stat and fan switch to run the engine at a slightly cooler temperature.

There's nothing wrong with my car mechanically, except for the dead heater circuit. Even then, the O2 sensor is still reading fine.

I will post an update in a couple of weeks. Meanwhile, good luck, JKL.

 

Dropping to 300 RPM sounds real weird. Have ur car checked bro... thats lower than idling speed.

 

Really? I did not know that! I thought it was normal. :P

Just messing with ya.




Dealerships are not happy with servicing my car due to my mods. Thus, I have to do a lot of things myself, but I accept it as the cost of modifying a car. Besides, it helps me learn about my own car and that knowledge is invaluable. I don't mind putting in the wrench-time. In fact, I'm always looking for excuses to put my car up on jackstands to go exploring underneath.

Like I said, if those possible solutions don't work out, then I'm going to have to take off my headers and take it to the dealership. But I think I'll be able to fix it. It's a mechanical issue, and that is soooo much easier than dealing with software issues.

 

I thought you didn know!!!

lol... Just messing with you..

Well, Good luck with fixing your car... .. and.. man.. thats BS... Aftermarket parts doesn break stuffs in cars....
Lazy dealer doesnt work hard enough.. too lazy too lazy..

 

Mine did the same thing last year, but mostly when cold. It turned out to be the IACV. So far so good. If not the IACV, I wonder if the throttle sensor could have anything to do with the low rpms and bogging?

 

Thanks Pure Adrenaline. I tried some Seafoam last night with no luck. I am thinking about to doing the same as you and take my headers off then bring my car back to the dealer. I just really hope the problem isn't from the headers so I can put them back on. Please keep me informed with anthing you find out. Thanks again!

 

Update: I just got my headers taken off and now my car is back to running smooth. My friend and I figured out that the flex pipe on the headers doesn't flex. It's so stiff It's actually like not even having a flex pipe at all. The flex pipe on my Stock A pipe is a lot looser so I think that the virating I was getting was because the flex pipe not flexing, so all the vibrations were getting sent through the whole exaust system. Thanks JKL.