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im posting this for a friend on his account. He just bought a 95 bronco 302 and after changing some gaskets on the upper intake and the valve cover gaskets it makes a loud mechanical whining noise. The car will run if we give it some gas but wont idle on its own. we checked vacuum lines and replaced the pcv valve. thought it might be starter not disengaging so we put a new one on. no luck. had a few ppl mention that it might have spun a bearing. we are hoping thats not the case. if anyone has any ideas that would be great

thanks
 

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Charlie don't surf..
'92 Ford Bronco XLT
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Loud whining could be the fuel pump going bad. Is the noise coming from under the hood?
 

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kinda tuff to diagnose from here, but if youve just had the intake off then its probly got a vacuum leak somewhere. and as for a whineing noise thats usually a rotating part, alternator, power steering pump, smog pump, a/c compressor, or something like that youll just have to listen real close. u can use a long screwdriver to find an area making the loudest noise. put the handle to your ear the lean into the motor putting the tip on the parts listed earlier. or get a mechanics stethescope from a parts store. JUST BE CAREFULL:beer
 

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Loud whining could be the fuel pump going bad. Is the noise coming from under the hood?
noise is from under hood. sounds like it is coming from the back of the engine somewhere. i really cant tell tho it definately sounds louder when i lay under the car near starter.
 

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kinda tuff to diagnose from here, but if youve just had the intake off then its probly got a vacuum leak somewhere. and as for a whineing noise thats usually a rotating part, alternator, power steering pump, smog pump, a/c compressor, or something like that youll just have to listen real close. u can use a long screwdriver to find an area making the loudest noise. put the handle to your ear the lean into the motor putting the tip on the parts listed earlier. or get a mechanics stethescope from a parts store. JUST BE CAREFULL:beer
i really dont think it is anything to do with the belt. sounds like its coming from back of engine. i know its kinda hard to diagnose online just looking for suggestions before we start ripping it apart. would having a vacuum leak cause it to make that kind of noise?
 

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its doubtful that a vacuum line would make a whineing noise, more of a hiss. and id drain the oil and check for metal, and from what youve said it dont sound good. i was hopin for you that the noise would be in the front of the motor, but from where you described it that sux. sorry dude! let us know what you find!!:beer
 

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Go buy an AUTOMOTIVE STETHOSCOPE ($20) at Sears or your local auto parts store. Usually they come with a solid rod at the end, which you touch to various parts of the vehicle to hear unusual MECHANICAL noises (metal on metal). The small price to pay for a tool that you can throw in your toolbox, and I guarantee you will use it at least another dozen times within the next 10 years.

What I did is take a small diameter steel brake line ($3 at parts store) about 12" long and cut the flare off the end and stuffed it in the end of the stethoscope's rubber hose in place of the metal rod. This allows me to hear AIR noises, like vacuum and exhaust leaks. Also because the brake line is metal, I can touch it to various parts to hear mechanical noises as well.

Ticks and knocks will transfer thru solid objects, so if you have a long screwdriver you could stick that up to your ear and touch it around various areas of the engine to try and pinpoint your noise.

It truly is hard to diagnose these sorts of problems over the internet, because of all the variables involved, including technical aptitude? But aside from an UNUSUAL coincidence, I would start looking at the areas that you worked on/around considering it didn't do this before the work was performed.

Good Luck.
 

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Driving Stuff Henry Built
-90 xlt, 351w, e4od, man 1356, 3.55, sag, warn hubs, 35s. -73, 400, np435, d20j twin, 35s
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Without hearing it, I'd be looking for a vacuum leak too, since you just had the intake off. I wonder if the gasket is in there goofy & sort of vibrating, causing the noise. Dieing at idle is also a symptom of a major vacuum leak. Like Worthy said, a stethoscope is great for narrowing down mechanical noises, but listening thru a piece of hose can locate vacuum & exhaust leaks pretty well on the cheap.

Check the pcv valve too. It normally flows vacuum thru it, & has a small piece inside that can vibrate if conditions are right. Double check vacuum hoses while you're listening.

Another scary possibility is that something was dropped down the intake during the work & is doing evil things inside.
 

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could it be a whistling you are hearing opposed to a whining? spray starting fluid around the intake to check for leak... and find the source of the noise
 

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its doubtful that a vacuum line would make a whineing noise, more of a hiss. and id drain the oil and check for metal, and from what youve said it dont sound good. i was hopin for you that the noise would be in the front of the motor, but from where you described it that sux. sorry dude! let us know what you find!!:beer
thanks.i decided to make my own account to where i dont have to hijack my friends anymore. im going over there tonight to try and see exactly Where noise is coming from and change oil hope we dont find anything in there.

could it be a whistling you are hearing opposed to a whining? spray starting fluid around the intake to check for leak... and find the source of the noise
definately sounds like a whine very loud goes with engine speed maybe i can get a vid up of it. we r a little nervous about running it for very long. we r going to go over all the vacuum lines tonight if the rain holds off.
 

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Another scary possibility is that something was dropped down the intake during the work & is doing evil things inside.
That was my thought too ... ?
 

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just left my friends house. i want to start off by saying i feel reallyreally stupid right now for missing this:banghead when my friend put the intake on aparrently a bolt didnt tightened down all the way. i must have missed it the other night cuz the sun was going down. i want to thank everyone for their input on the problem. im very glad that we found this site. thanks again
 
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