I have an 88 s10 2.8l 4x4 and the air pump seized. I found a shorter belt
> which allows me to just by pass it but my question is what does the pump do?
> If I plug the hole in exhaust manifold and by pass the pump will it still
> run well or what would or could the consequences be? Will it idel high or
> kick and sputter, just what would it do?
>
>
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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