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Old 11-06-2009, 03:51 AM   #1
dlh1999
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Default Leak causing knock?

I've had a couple CEL's lately that have all been MAF related. I know that the MAF is fine, but after pressurizing the inlet to find leaks, I've found one on one of the elbows coming off the inlet. Also, some of the IC couplers seem to be a bit worn, and might be leaking as well.

Would a leak in the intake system cause a lean condition, which would in turn cause knocking and/or lower IAM's? Recently I've done some logging, and definitely have some knock...I'm just hoping that maybe a leak somewhere might cause this...at least it'd be a relatively easy fix. Any ideas?
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Old 11-16-2009, 06:15 PM   #2
awd4ever
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I am curious about OP question that as well.

Also, how did you search for leaks? In the rx7 days I used to spray wd40 on joints and listen for idle to go up. It doesnt seem very precise, but it would find some larger leaks.

Thanks,
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Old 11-16-2009, 07:20 PM   #3
RaceFaceXC
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any leak after the MAF can cause problems, however with a turbo when under boost, leaks will result in less than the MAF measured amount of air reaching the cylinders (rich condition) and while under vacuum the opposite typically occurs.

A WB is highly recommended and really required to tune beyond CL maf scaling and OL/CL delay zero-ing
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