header guestion?
 

would the engine light go on if i put headers on. cause the vacuum pipe that connects to the origanal manifold has a hole that connects to the exit of the manifold. but the aftermarket header does not. its like sealed! is that a problem?

Are you talking about the secondary air injector port? Then yes, you will throw a code for sec air eff.

Sec air mixes with excess hydrocarbon at cold startup to more quickly get the cat up to temp. If you dont have a cat, then it really doesn't matter.

Lots of folks delete the sec air. Access port deletes the code.

well then whats the use of it being closed on the header? does it make for better performance? whats the purpose. why not just keep it opened so u dont throw a code?

Better question is why do you want to put a header on there? Does it make for better performance? What's the purpose? Why not just leave the log manifold on there so it doesn't throw a code?

Header will gain you nearly nothing, particularly if you still have the stock cat. It might sound a little better. Mine did when I had it on there. But there is no significant power there.

Deleting the sec air loses weight and gives you a little more space under the hood.

o ok i see.. an the reason why is cause my stock manifold with the o2 senosor is seized up in there an broken an all i had layin around was headers when i bought them before i turboed my car. i sold my turbo an put the stock manifold back on an couldnt get the o2 sensor out. so i bought a new sensor an put it in the headers. only prob i didnt no that the sec air would throw a code.

I have a manifold I can sell you. Price is in the WTS section under my name.