Vacuum leak?

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SUSPECT 0
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Vacuum leak?

Post by SUSPECT 0 »

At idle I can hear a "hissing" noise coming from the throttle body and I have pinpointed the noise at the EGR tube inlet to the throttle body.

Is it normal to hear a hissing noise come from this tube or do I have a vacuum leak?

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Re: Vacuum leak?

Post by 00Beast »

It's pretty normal for them to crack. They're a PITA to find too...
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Re: Vacuum leak?

Post by willwren »

Remove it and carefully inspect for cracks. If the tube is cracked, you'll need a replacement from a 94 or 95 ONLY. 91-93 will not work without leaking. You might be able to have it carefully welded by a true pro. Tell us what you find.

That leak will cause you to run lean, so stay out of the boost as much as you can (no WOT at all) and make sure you're running the proper octane (as always, never lower than 91).
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Re: Vacuum leak?

Post by J Wikoff »

Get some high temp RTV and fill up the space between the tube and the mounting tab. Let it dry well before you start it.
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Re: Vacuum leak?

Post by SUSPECT 0 »

I always run 91 octane, I'll pull it off and see whats going on, if it's a minor leak I might slap some silicone on it.
Last edited by SUSPECT 0 on Sun Mar 20, 2011 10:55 pm, edited 1 time in total.
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Re: Vacuum leak?

Post by willwren »

Use the red snot, but if the tube itself is cracked, RTV won't solve your problem.
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