AIV/PRVR/EGR removal
 

since my plenum is out, im thinking of considering these removals. i found a write-up for it already, but im worried about any adverse effects that could happen. im wanting to do this mainly for the engine clean up (damn hoses everywhere!) and easier time to take the plenum off if i have to do it again

Definitely remove the AIVs if you get an aftermarket ECU. The EGR I would be hesitant to remove for fear of not passing emissions. The PRVR, I have read, is supposed to prevent vapor lock. So remove at your own risk. People have done it with no problems.

I have yet to read about a real benefit of removing the PRVR system.

Like the dude said,....remove the AIV and leave the EGR. In order to remove the AIV, you really need to replace your cats or remove them all together.

Yugobernie on tt.net sells plugs for the cats. I got mine from him.

Do you not need a ecu upgrade in order to remove the AIVs ?

You need one, otherwise your stock ECU will think the AIVs are still in place. You need an ecu with the AIV delete program. JWT and ASHspec have it.

The reason I say that you should upgrade your cats is because the pre '93 cats need the AIV in order to operate correctly. The older cats need to have air injected into to them in order to assist in burning the unburned fuel. The newer cats do not require the AIV (aka smog pump). ZXdude, have you smogged your car since you removed your AIV's? I wonder how much of a difference it really makes and if you'll be able to pass smog.

I havn't since I physically removed the system, but my ECU already has the AIV delete feature and turns the system off anyway. When I got the car, it already had the JWT ECU and the guy at the emissions place said it tested like a new car. If you get these plugs http://www.twinturbo.net/net/viewmsg...d&msg_id=86155 (open and scroll down)
you shouldn't have to worry about getting the 93+ cats. You can either do that or leave the units under the fenderwells, put a golf tee in the vacuum lines that go up to the solenoid and just remove the AIV stuff in the engine bay.