The air pump feeds fresh air into the exhaust at idle and when you let your foot off the throttle. This helps burn raw fuel in the exhaust and lowers emissions. It doesn't hurt performance or fuel mileage as at higher rpm it just coasts like an idler pulley. Can you do as you requested, probably yes, however it could cause erratic input to the ECM from the O2 sensor when the exhaust goes rich.. If the ECM leans the fuel mix out to much trying to compensate you could have drivability issues. Will you pass emissions test if its in your area, no. Pump costs $41.99 from autozone.
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