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DISCUSSION => Engine management => Topic started by: 16v of E30 on November 03, 2008, 02:36:55 AM

Title: Hissing noise at startup
Post by: 16v of E30 on November 03, 2008, 02:36:55 AM

Happends occasionally, when i start the car. Usually when i turn the car right over, i get a hissing noise under the hood, but the car always starts without hesitation.  anything like this happen to you?

Title: Hissing noise at startup
Post by: Cobra Jet on November 03, 2008, 09:34:44 AM

Nope.  

Check any or all rubber vacuum lines under and around the intake (both upper & lower).  Also, check the large rubber air intake tube going from the headlight bucket on the driver side to the airbox assembly - this tube is known for cracking due to age & engine heat.

Title: Hissing noise at startup
Post by: JP 91iS on November 03, 2008, 12:03:00 PM

Well if the car starts without hesitation and idles fine I wouldn't suspect a vacuum leak.  You should have someone else start the car while you listen around the engine bay, maybe its not really a hiss.

Title: Hissing noise at startup
Post by: 16v of E30 on November 04, 2008, 12:17:01 PM

yeah its weird...happens one in 5 startups...

was thinking it was fuel lines getting primed?

Title: Hissing noise at startup
Post by: EN318isPDX on November 04, 2008, 01:55:24 PM

Quote from: 16v of E30;60033

yeah its weird...happens one in 5 startups...

was thinking it was fuel lines getting primed?

Could be, fuel likes to make a hiss noise when it leaks.. I'd start looking for fuel leaks

Title: Hissing noise at startup
Post by: 16v of E30 on November 07, 2008, 05:53:23 PM

no leaks...