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Old 12-04-2023, 03:58 PM
Serb404 Serb404 is offline
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Quote:
Originally Posted by 80stech View Post
I guess it's possible that the air pump might only be noisy if there is extra back pressure from the exhaust ?? Does it seem to change with that in mind ? (on coast or accel)

You should be able to hear the air pump running on a cold start and then maybe listen for when it quits before driving away so you get an idea of what it sounds like.
Air Pump runs perfectly, no whistle noise from that at idle, when I'm coasting around 1.5 rpm it makes a slight whistle, goes away after 5 minutes of driving, I can try to grab a video of it possible to help further diagnose

Quote:
Originally Posted by andrewwynn View Post
There is the valve that goes from sap into the exhaust. If that isn't opening full or some other issue I could see it making a whistle. Too coincidental of the cold start and 90-120 seconds to really be anything not sap related.

Usually the bearing fails and it will make a horrendous noise like the car is trying to hover.
yeah I've had that replaced a long time ago I believe, it was a horrendous sqeaking noise on cold starts, was extremely bad in the winter too
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