A friend and I installed my vibrant header and down pipe today, it was a tight fit but it went, there is a problem though. I am hearing a noise (sounds like a belt squeaking but its not) coming from the driver's side of the header. Thats an exhaust leak right? The sound goes away when it is heated up though, like running it for 2 minutes or so and the noise goes away. It is only around 1100 rpm that i hear it then i just hear it when i shut the car off. If it was an exhaust leak wouldn't it do it the whole time through out the whole rpm? I went through and tightened everything a little more and it still did that. Any input?

 

did you use the old manifold gasket or did you replace it?

 

I replaced it, and made sure i put it on the correct way.

 

I fixed that problem, now i think i am just hearing resonation. I drove the car about 50-70 miles and yesterday right after i pulled into the parking lot at work the CEL came on. I tried scanning it with EZ scan 6000 but it said vehicle was not responding (it needs updated though i believe). So i just reset the CEL by disconnecting the battery and while i was doing that i took an inspection mirror and a flash light so i could see any black spots from exhaust leaks....their were non. So, do you think the CEL was a fluke or does this just not like my header and dp? I drove the car right after for 30 miles, both highway and through town and the CEL isn't back on....yet.

 

Check the collector/downpipe flange gasket. I overtightened mine and crushed the gasket so it leaked. I put a new gasket on and it was alright.

 

So helltime how do you feel about your mods so far? Does the car perform much better...do you think it was worth the investment? Reason im asking is ive been tossing around the idea of doing the same mods youve done on my 07 cobalt.

 

I like them, but like others i want to do so much more. Today my car got screwed up (back bumper) so i have to repair that before i do anymore (its a new car, and it makes me sick to see it damaged) but what i did so far was defineatly worth it to me. If i could have gotten an actual "Project car" i would have been happier (something with a V8, like a fox body) but i couldn't so i decided to toy with my car, it was cheaper that way and it is good to have a fun daily driver. The cold air intake was my first performance mod, it made a difference in the higher rpm but above 5k still seemed iffy....then i got the cat-back and was kinda upset because i thought i had just wasted money, i got about the same amount of gain (maybe a tad less) then my cai and at double the price, but it is essential if you are going to do anything else to the car performance wise, then i got my header and downpipe, this has by FAR made the most difference, it feels like i lost alittle in the lower rpms, but i gained alot in the higher rpms, this car is flat out fun to drive on the highway now, i enjoy it on the highway more than i do my dad's 83 5.0 stang This thing goes pretty go all the way up to redline and pulls nice. All depends, on what your goals are.

BTW: No check engine light anymore (reset it and still hasn't come on in over 100 miles) and no exhaust leaks found at this time