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Old 01-31-2010, 04:32 PM   #16
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does that valve on anyones car rattle mine makes a rattling nose sometimes when i first start the car
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Old 02-01-2010, 12:08 AM   #17
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The rattling people usually hear when the car first starts up is associated with the secondary air pump.... The pump usually shuts down shortly thereafter and the "rattle" goes away. If that describes the rattle you're hearing, then check the secondary air pump.... it shouldn't rattle..... Otherwise, not sure what's rattling...
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Old 02-01-2010, 02:37 AM   #18
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Originally Posted by arsevader View Post
Dunno who told you this but it's baloney.

The secondary air pump is what heat the cats up upon cold starts. That flap doesn't really restrict all that much. Certainly not enough to heat up the cats. A restriction that far upstream that was enough to heat up cats would be a cause for concern.
Not that much, just 50% of the final exhaust size!
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Old 02-01-2010, 07:57 AM   #19
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Thx EuroStyle; someone gets it..... This thread wasnt started to create a discussion on the relevance of the blockage, but to inform Max members of a potential issue with our e46s that most people (including myself) would not typically check. The results of removing the blockage are nothing short of amazing!.. With the blockage you have a 50% restriction in the amount of air the car can "push through". Air that can't be exhausted, builds up and creates backpressure which the engine fights to produce HP. Thats why guys spend over $1000 to replace existing exhausts.... the primary way those systems produce more HP; reduced back-pressure = more airflow + more noise..... A 50% reduction in output capacity from the exhaust will have NOTICABLE reductions in power (HP) because the car won't breathe properly and I found it particularly noticable @ RPMs above 2,500....

A note to all Max members that read this thread; don't debate, just check the exhaust valve function and remember to check as part of your maintenance!!! Thats it!
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Old 02-01-2010, 09:58 PM   #20
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Good Advice nachos23

Mine has been stuck open for over a year now i guess I'm lucky its not stuck close
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Old 02-02-2010, 01:13 AM   #21
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stuck open; you're laughing...... I was thinking about the Golf-T mod, one of the reasons I was looking @ it to begin with..... now I have it permanently...... LOL
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e46, exhaust, performance

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