put it on yesterday and it fluctuates between 1,000-500 RPM. is this normal for it to idle that low after installing a header? i still have stock exhaust and a fujita SRI. i also used a new manifold gasket. any help is greatly appreciated

 

that is a huge fluctuation. make sure you bolted on things tight and that there are no leaks, as a leakage might be causing that flux.

 

Sounds like somethings wrong with ur O2 sensor.

 

everything is tight. if it was my O2 sensor wouldn't my check engine light be on?

 

An O2 sensor doesn't have to throw a cel in order to be bad. It's suppose to throw a cel when it goes out but most of the time they wear out just enough as they make the car not run right yet don't throw a cel.

My first car, 1989 Oldsmobile, had a bad O2 sensor and everytime I went to floor it the car would backfire and then stumble before it would go. Drove around for almost a year b4 I replaced it which solve my problem.

My dad's 98 Camry, we went to change to O2 sensor on it and turned out the parts guy gave us the wrong one. The car had a bad idle surge when we used an aftermarket O2 sensor and went away with the old O2 sensor reinstalled untill he got a new factory one.

 

did u do a ecu relearn???..that might be the problem..i had that problem when i installed my exhaust and air intake..disconnect the battery for a bout a minute..the start the car up let it idle to the radiator fans cycles twice..the go drive it for like 5 minutes..then shut the car off and restart it..it should idle ifne after that..reason being..the o2 sensor is now in a slightly different location then stock..plus the size of the header tubes are different then stock..cause the o2 to wig out...do this ans the idle will go back to normal..trust me ..i'm a honda tech..see this all the time on civics, accords, and s2000's...

 

I haven't tried this yet. what do you mean by letting the radiator fan cycle twice? the fan actually turning on and off twice? thanks for the tip, i hope this works

 

What's the chances is from him still having the stock exhaust? Cause we did mine header the same time, but I already have a DC exhaust, and mine idles fine. I was thinking the engine is exhausting more gas, but is being restricted at the end with the stock exhaust. Does this sound like a probably cause? I don't see it being his o2 sensor cause his box is almost brand new still.

 

it could be do to the stock exhaust..due to the size of the header tubes and the new location of the primary o2..plus since this vehcile is obdII compliant..the primary os is not a o2 it's a air/fuel ratio sensor and the one after the cat is the o2...so like i said in my last post..follow those steps and it should idle fine..also check your air intake and make sure u put the mass air flow sensor in correctly..that will also cause a erratic idle...