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hey guys, I searched the forums and googled it but I cant find what Im looking for and I dont have time to do more searching because this is my everyday car so I'll just ask

I changed the exhaust manifold for a cheap aftermarket one and the AIG tube wouldn't fit and neither would the EGR, so I welded shut the AIG and got rid of it and left the EGR hanging there and I dont want to weld it off too because I dont know how necesary it is, I know that if I dont use it my fuel eficiency would drop some but I dont care, and also, If I weld off where the EGR goes into the manifold, What do I do with the EGR tube? do I close that off?
Will it have an adverse effect on engine performance, or will my ECU just throw a code?

thank you
 

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yeah, the EGR is useless as far as preformance goes, just unscrew the plug and stick a nickel in there and it plugs it right up. and you can remove the AIV and it will clean your engine bay some
 

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after searching i didnt find what i was looking for..but what is the AIV/what does it do?
 

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its supposed to put clean oxigen backinto the exhaust for the catalist to use in braking up hydrocabons or NOx or CO, Im not sure, but on this older cars the valve can malfunction because its so old and it can let gasses into the intake and it can cause a rough ride. Primarily its used in high altitude places where air is thin and oxigen is scarse, just as its harder to breath because of the lack of oxigen, the engine finds it hard to get oxigen burns all taken in and it makes it hard for the catalizer to break up the toxins having little or no oxigen, thats why the car puts oxigen into the exhaust manifold. in a low altitude place, like the coast, it is basically unnesessary because the concentration of oxigen here is high, so not all burns up.
That was the AIV, what he was asking about was the EGR, and that is the system that actually puts exhaust gasses back into the intake for another combustion, and that would be the upper tube you see coming out of the mani, the AIV tube comes out of the mani near the steering column further down.
 
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