Hissing Noise

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Mar 11, 2008 | 07:56 AM

bowdog

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From: Western Pennsylvania

Hissing Noise

Hey Guys:

Noticed when I was changing the oil the other day that when I turn my truck off, there is a hissing or tinging noise coming from the driver side engine compartment. I looked around and saw no leaks, Any ideas what it may be? I have a 98 F150 4x4 4.6.

Thanks

Bowdog

Mar 11, 2008 | 09:05 AM

projectSHO89

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From: St Louis

Try to pinpoint the source while it is making the noise.

Mar 11, 2008 | 09:32 AM

ground_zero298

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Mines been doin that for years, nothing has ever come from it. I figered it's just built up air in the cooling system.

Mar 11, 2008 | 09:32 AM

Joe Finn

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From: DC

I think the noise you're talking about is normal. Mine does it too. I always thought it was "left over" vacuum in the heat / AC controls, but I don't know for sure.

Mar 11, 2008 | 09:49 AM

bowdog

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Joined: Jan 2008

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From: Western Pennsylvania

thanks guys....I wasn't sure what it was....it has me stumped...I do know that there are no fluids leaking anywhere. just an annoying sound that alerts you to a potential problem.

I will monitor it and see if anything comes of it

Happy Trucking!!!!!

Bowdog

Mar 11, 2008 | 10:12 AM

Club Wagon

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Was the "hissing or tinging noise" new? Now that you've "noticed" it does it happen every time?

You can eliminate "left over vacuum in the heat / AC controls" OR "built up air in the cooling system" & check for other sources. To dump vacuum press the brake pedal several times until the vacuum reserve is used up. To eliminate AC refrigerant noises turn the AC compressor off (OFF, FLOOR or PANEL) & leave it off for awhile (overnight to be certain, but an hour should do) before listening for the sound.

A "tinging noise" is normal on my '98 F150 4X4 4.6 but is the common sound of exhaust system cooling.