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High pitch whistle coming from engine bay

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Old 10-08-2010, 09:19 PM
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Exclamation High pitch whistle coming from engine bay

Ok i wanna start by saying NO it is not a belt squeak and NO it is not a bearing in anything. it sounds more like its coming from the back area of the engine bay, maybe a little more towards the dr side.. its kinda hard to tell thiough. im pretty sure its a vacuum leak of some kind cause when i give it a little gas it stops. its actually like a really high drawn out beeeeeeeep noise. ive checked most of the vacuum lines up top and where i can easily see or reach. does anyone have any idea what this noise is? could there be other vacuum lines or areas i cant see or reach somewhere? PLEASE HELP!!!!! this is the most annoying noise in the world! i stopped at a red light the other day and an old man rolled up his window lol! people stare at me and i know its not cause of the sexy driver or kick *** ride. its hurting my relationship with my jeep sadly.
Old 10-08-2010, 09:24 PM
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I would check the gasket between the intake and head. It could also be a very small exhaust leak. Easiest way to check for the intake leak would be to use a can of either or an unlit propane torch and use it around the gasket, see if your idle changes.
Old 10-08-2010, 09:25 PM
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Aftermarket air intake with a cone filter?
Old 10-08-2010, 09:55 PM
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nope all stock stuff ^.. i was thinking it could be the intake gasket too. i figure if its the exhaust it would flutter more but this it a good steady loud friggin whistle. ill check all that in the AM i plan on doing some wrenching around tomorrow anyway
Old 10-08-2010, 09:56 PM
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+1 for another silver jeep btw!
Old 10-08-2010, 10:06 PM
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Silver 2000 Cherokees are the best.
Old 10-08-2010, 10:13 PM
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get a can of carb cleaner and while its runnin spray alittle around vacuum ports and the intake flange. if the idle goes up look there for a leak. and if you cant find any vacuum leaks it could actually be a dirty throttle plate and or iac. ive seen fords do it
Old 10-08-2010, 10:16 PM
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Originally Posted by Defiance665
I would check the gasket between the intake and head. It could also be a very small exhaust leak. Easiest way to check for the intake leak would be to use a can of either or an unlit propane torch and use it around the gasket, see if your idle changes.
Originally Posted by btownxj
get a can of carb cleaner and while its runnin spray alittle around vacuum ports and the intake flange. if the idle goes up look there for a leak. and if you cant find any vacuum leaks it could actually be a dirty throttle plate and or iac. ive seen fords do it
x2....
Old 10-08-2010, 10:33 PM
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what does x2 mean? yea after i posted that i saw you said he same thing. thats what i get for scrollin too fast.
Old 10-08-2010, 10:35 PM
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pretty much means "i agree"; I was using it for sarcastic effect, of course...
Old 10-08-2010, 10:40 PM
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x2 = times too. = me also

throttle plate? where it mounts to the intake? or the butterfly valve in the TB? the previous owner replaced the TB thinkin it would help but no candy.. so now i have a spare. ill do the carb cleaner thing tomorrow. im gonna find this if it kills me cause if i dont it will anyway lol
Old 10-09-2010, 07:20 AM
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yea check the throttle body gaskets and make sure the bolts are tight. if that all looks good take off the inlet tube a give the throttle plate itself a good cleaning. i like to save my old toothbrushes and use them with some carb cleaner. the toothbrush is cool cause you can use one hand to hold the throttle open and the other to scrub. it will be hard to start after cleaning. crank it over and press the throttle thatll help.



Originally Posted by Defiance665
pretty much means "i agree"; I was using it for sarcastic effect, of course...
gotcha im new to the whole fourms thing. thanks

Last edited by btownxj; 10-09-2010 at 07:26 AM.
Old 10-09-2010, 10:43 AM
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I have this same issue and I agree, its annoying as heck..happens when i accelerate and when I turn it off. Hope you find the problem soon.
Old 10-09-2010, 11:23 AM
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88mj mine kinda does the opposite.. i can go out side and fire it up and it sounds perfectly normal for like 3 mins but then after its warm this beeeeeeeeeeeep kicks in. engine sound doesnt change or anything and the fans were already on. then i can grab the throttle linkage and barely give it any gas and it quits, goes away like nothin ever happened
Old 10-09-2010, 01:18 PM
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same thing was happening to one of my friends. The exhaust manifold gasket had a crack in it and that caused the "whistle".


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