Author Topic: Vacuum Leak  (Read 8139 times)

Offline team39763

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Re: Vacuum Leak
« Reply #15 on: September 30, 2009, 08:43:38 PM »
No air injection.  Doesn't look like it ever did.  I don't see a EGR valve or anything. I have both valvecovers coming together at one T-fitting and then venting to the throttlebody.   

Offline team39763

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Re: Vacuum Leak
« Reply #16 on: October 01, 2009, 09:53:29 AM »
I think I'm gonna try adding a valvecover breather/filter.  When I took off the oil cap, the whistle went away, so maybe the motor needs better crankcase breathing?  I'll give it a try and see what happens.

Offline VileZambonie

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Re: Vacuum Leak
« Reply #17 on: October 01, 2009, 10:23:19 AM »
Wait, you have both valve covers going to a vacuum source? That's a no no. One should be a PCV valve with a hose going to the large vac port the other should just be a filter vented to the air.
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Offline team39763

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Re: Vacuum Leak
« Reply #18 on: October 01, 2009, 07:08:07 PM »
That's how the truck was when I bought it, but I just fixed that with a filter.  I'll see how it sounds in a bit.