Odd exhaust sounds at idle/warm up
12-11-2011, 03:54 PM
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Odd exhaust sounds at idle/warm up Howdy, Folks. I've got a 1998 Z28 Camaro, with 166,xxx miles on it. I'm the third owner of this particular car, and I've been hearing this noise for a couple weeks now.
At start up/ idling, I can hear what I believe to be a fan of some sort coming on, and then a change in the exhaust sound. It's a sort of WHUH WHUH WHUH WHUH sound. It'll do that for a few seconds, stop, and do it again until it gets up to a good running temperature. I'm not new to F-Bodies, and I know the LS1 is prone to its random ticks and such, but I've never heard an LS1 powered car make this noise. I haven't noticed any sort of decline in performance or fluid pressures. It's pretty much bone stock, save for the air filter and box.
Anybody got any idea what could be causing this? Any help would be appreciated.
At start up/ idling, I can hear what I believe to be a fan of some sort coming on, and then a change in the exhaust sound. It's a sort of WHUH WHUH WHUH WHUH sound. It'll do that for a few seconds, stop, and do it again until it gets up to a good running temperature. I'm not new to F-Bodies, and I know the LS1 is prone to its random ticks and such, but I've never heard an LS1 powered car make this noise. I haven't noticed any sort of decline in performance or fluid pressures. It's pretty much bone stock, save for the air filter and box.
Anybody got any idea what could be causing this? Any help would be appreciated.
12-11-2011, 04:02 PM
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I am guessing you are hearing the air pump. It comes on at startup and adds air to the manifolds to heat the cats up quicker. Then it turns off. Maybe it's starting to go out.
12-11-2011, 06:00 PM
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Sounds like the AIR pump to me as well. Sometimes mine will cut back on for one or two seconds after it's already cut off, I don't know why but it's always done that. I don't worry about it.
