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Discussion Starter · #1 ·
Got an interesting situation with the R: <p>Within the last couple weeks, when I nail the gas and accelerate hard it sounds like my car has some crazy cold air intake or something! It's a rush of air that seems to either get sucked in or is being forced out somehow. The harder you gas it the louder the sssssssssssssssssssssss sound, though under mild or moderate acceleration it's not noticeable.<p>Recent mods include the Phuz DP (2 months ago), IPD Boost Gauge (1 month ago) engine blankie removed (1 month ago) though this problem was not noticeable after any of these mods, only just recently.<p>I'm thinking an exhaust leak (perhaps the DP flex joint)? Would a failing head gasket produce a hiss like this? Maybe something to do with the boost gauge/lines? I popped the hood this evening and had the wife stomp the gas and the hissing seems to come from the engine bay as opposed to down the exhaust line somewhere.<p>Thanks for helping me find a good place to start problem solving guys!
 

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Re: Hissing sound from the front while accelerating hard?? (Capital R)

It might just be your turbo spooling up and you didn't notice it before
 

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Discussion Starter · #3 ·
Re: Hissing sound from the front while accelerating hard?? (cuseR)

While the turbo is MUCH louder, it definitely isn't the turbo. Spool and the hissing sound occurs simultaneously.<p>Envision windows down, stomp the gas, and hiss like a snake very loudly.<p>
 

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Re: Hissing sound from the front while accelerating hard?? (Capital R)

I would look at the turbo to downpipe connection and the over engine pipe connections to the turbo and intercooler.<p>Cheers,<p>Jeff
 

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It sounds like you have a vacuum line disconnected.
 

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Re: (phuz)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>phuz</b> »</i></TD></TR><TR><TD CLASS="quote">It sounds like you have a vacuum line disconnected. </TD></TR></TABLE><p>Yes. <p>Let's start small here. I doubt it's a big problem. <p>Problem with this board is that people tend to jump to the worst conclusions. "I hear a noise, it must be my angle gear going!" No, it's probably just worn / cupped tires. <p>Chances are it's nothing big, especially since you have several mods (DP, blanket removal) that increase the aural presence of the turbo spoolup.
 

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Re: (Capital R)

Try this, I have the same sound, and it has done it the whole time.<p>Does it also happen while you're cruising on the highway, and you open the sunroof.<p>It's definitely more predominant with the Phuz DP, but still, try that. I think its the ventilation system. I've noticed all kinds of weird things, like feeling air coming out of the seat belt hole with the sunroof cracked. I think the same thing happens, like theres a vent door that is weak, at high speeds.
 

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Re: (Capital R)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Capital R</b> »</i></TD></TR><TR><TD CLASS="quote">Wouldn't my boost gauge be affected if the problem was a vacuum line?</TD></TR></TABLE><p>Probably not enough to notice, though it depends on the line that's off. I bet that, if you only notice it when under power, it is a junction to your OTE (either side).
 

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For future reference, exhaust leaks generally don't hiss, they're much more of a ticking or puffing sound. Much more likely an intake leak.
 

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I got this same hissing sound increase when I installed the IDP (RKelly) CAI. I thought it was related to this so I have never checked anything else. <p>Do I need to be concerned?
 

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Re: (prancing_moose)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>prancing_moose</b> »</i></TD></TR><TR><TD CLASS="quote">I got this same hissing sound increase when I installed the IDP (RKelly) CAI. I thought it was related to this so I have never checked anything else. <p>Do I need to be concerned? </TD></TR></TABLE><p>No.
 

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Re: (Needsdecaf)

Check **all** your Phuz connections, ensuring you have all your T-bolts on correctly and all connections haven't slipped and are tight. Dave_n_Ruth on this board recently diagnosed my issue which sounded (no pun intended) EXACTLY what you are hearing, and it was a disconnected coupling on my Phuz FMIC setup between the drivers-side pipe coming out of the right side of the FMIC and as it turns up and towards the left - connecting to the black plastic pipe. I has a 1/4" gap!!! We reconnected this union and tightened my T-bolt, and my car is a speedster now - achieving full boost as well...before, I was not and got so used to it, I thought it "normal". So if you also have a boost gauge, this is an excellent secondary indicator of a large vacuum leak, which sounds exactly as you described.
 
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