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Old 08-15-2011, 09:46 AM
TimFreeh TimFreeh is online now
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Join Date: Aug 2001
Location: Milford, DE
Posts: 1,573
Quote:
Originally Posted by alphanumeric View Post
..... I hear the rattle in the ranges of 1-2k rpm in all shifts, 1s, 2nd, 3rd, 4th in the city!. when I was driving down the street going say 35-40mph, I can hear it really good when I pass parked cars. it goes away when I left off gas. but once I press on the gas, I hear it immediately. In the city, my rpm range is always 1000-2000rpm casually driving and maintaining speed, and that rattle is constantly making nasty noise..
That's kind of strange because during normal operation I don't think the ECU engages the supercharger at all until the engine reaches 2050 RPM. As we've noted before the ECU will use the supercharger as an air-pump in warm-up mode but I don't think the supercharger is normally engaged in the 1-2K RPM range.

Are you sure the rattle you are hearing is coming from the supercharger? Did the noise disappear when you disconnected the belt?
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