Put on header, now bad idle...
 

My friend put on a pacesetter header on his 7 and now it won't idle most of the time at all. Any ideas?

did you disconnect the air pump and block it off, if not try that and see what happens

Now, be carefull unhooking the air pump if your "friend" still has a cat.

Cory

o2 Sensor maybE? or lack of?

Lol man, it really is my friend. Oh ya, he also took out the stock filter and drilled holes in the stock box. Don;t think he did anything with the airpump or anything though but I never did with mine except put some screen over the tube and mine was fine.

Umm... IIRC the pacesetter does not have an O2 sensor attach point - did you leave the O2 sensor out? If you did, it won't run well. :D

You can get an O2 sensor "bung" (yes, that's what they call it) and have it welded into the header (or even behind the header) for probably $30-40 bucks, maybe a little more. Luckily O2 sensors are cheap. You may have to do a little wiring if you put it too far back.

02 sensor is not used at idle. Did you knock off the vacuum lline for the Boost/pressure sensor while installing the header????????? Or any other vac line in that area like the one to the cruise control??? Knock off any of the two vac lines that go to the acv????? The vac lines at the water thermo device on the aft end of the throttle body???????????? Knock plug off the pressure/boost sensor???? Leave one of the clamps on the intake duct loose???

I really haven't looked and wasn't the one that installed it but will ask him.

I know when I put the header on my car it ran like crap for about 3 days

then one day I got pissed off at it drove the shit out of it and it has ran fine ever since

You know what, I got to my friends house and he said sumin was fucked up and that it wouldn't idle but he wanted me to race his brothers FC. So we went out and about for like a few miles and raced about 10 times and then it started to actually hold an idle. Maybe with some more stress it will run better and better. That header is a POS though, it looked SS but didn't after the first time the car was ran, lol.

Deffinitely sounds like a knocked off vac line somewhere. If the only change was a stock manifold to a header, your idle should not change. Getting your hands down in there is preaty tough with the stock manifold on, I think I pulled a few off when I changed mine.

WOW! remember the stock manifold ...

i dunno whatchur talking about. my pacesetter had a bung in it that u bolted a o2 sensor into. fyi

scott

I wish I was there to help him so I could have a better idea what he did. Oh well I will tell him to look for broken vac lines.