lpsgslse

Hi all. I need some knowledge. On the GSL-SE...What is the purpose and function of an air pump & air control valve? Also, if these two items have been removed from a vehicle, what affect would this cause to the car? (Good/bad) Lastly, will it be simple or difficult to restore the two items back into the car? Thanks.

black_sunshine

The air pump and ACV simply injected air and some unburnt hydrocarbons into the catylatic converter. On the lower intake manifold, there should be a tube going from there to the cat. Just make a block-off plate for the ACV and remove the air pump (block-off the hole left in the air box). The pros: reduces weight and a minimal HP gain. Cons: not emissions-legal and can cause you not to pass smog. So, if you don't have to smog test your car, take it off. Also, block-off the EGR valve (under the intake manifold) and remove the vacuum/solenoid rack for the full effect. Make sure to cap the cavuum sources off, and make sure your FPR has a vacuum source (or even the solenoid if you wanted).

lpsgslse

I see. What is the FPR?

black_sunshine

Fuel pressure Regulator; it's attached to the fuel rail and has a vacuum hose going to it. Basically, the vacuum your engine produces (full vacuum at idle, and no vacuum at wide-open throttle) determines the pressure your fuel injectors receive. More vacuum = less pressure; it (the FPR) really helps to fine-tune the idle/cruising air/fuel mixture. When I remove all the emissions stuff, I just hook the FPR to a spare vacuum nipple (similar to how every other car I've ever seen is hooked-up).