Whining Noise from under the hood?

[BigRedRangerII]

Hello,

I have a whining noise coming from under the hood. It seems to worsen when the heater is turned on. It also is only noticable when the Truck is at idle, or I am not engaging the throttle. For instance, if I am sitting in traffic I will hear the noise (a constant whine), and usually the engine will rev up and lurch a little bit. If I flip the throttle the noise and the reving go away (usually). Any thoughts on the problem would be greatly appreciated. Thanks.

Specs:

2002 Ford Ranger 2wd 4.0 L

 

[Ranger44]

Power Steering Pump? Check the seal where the pitman arm attaches and the fluid level. First thing I can think of off hand.

 

[BigRedRangerII]

Thanks for the info. I will check that out, although I recently checked all of the fluids. I was thinking it might be a bearing in the ac or water pump, was going to try using wd40. any thoughts?

 

[87Ranger4me]

If the pitch of the whining changes when you turn the heater or headlights on, then it's your alternator making the sound. When mine started doing that it was only a few weeks till the alternator went out completely.

 

[BigRedRangerII]

I was just driving to lunch and it made the sound with out the heater being on. I wonder if the alternator is the culprit? You say if I turn on the lights the pitch should change, I will try that the next time it happens. Thanks for the suggestions.

 

[BigRedRangerII]

Checked out the suggeestion and no luck. When the sound started I turned the lights on, and the pitch did not change sound. I then turned on the ac and no change in the sound, however the truck did lurch when I turned the AC on.

However the sound comes on regardless whether the ac is on or not.

mystery to me still.

 

[woodyedmiston]

Just guessing here?!?

I've had two "whines" from under my hood that were baffling. One was the camshaft position sensor - the little dude that sits where the distributor used to sit at the back of the intake manifold before there were electronic ignitions. The bearing goes bad and intermittently makes a screeching sound. Replace it and the screech goes away.

The other is the filter box. If the top is not on just right, it will "moan" at idle speed and go away when you jazz the throttle. A little Armorall or something like that on the gasket and a tight hold down will stop it.

However, I'm not at all sure that fixes it - or even if that is where the noise is coming from. Sometimes it will make the same noise right after I think I've stopped it. I'll bump on the box and it will stop. I've been running the same alt, ps pump, for a long time and they haven't failed. Both have been changed out and it does not stop that sound. Everything else that rotates has been replaced . . . and I'm still bothered with the noise from time to time.

 

[Barber]

My wifes Explorer does the moaning thing.... but only when it's hot outside.... as in 85+ temps... pull up to a stop, and it goes to moaning... sometimes even killing the engine.... Pull out and it quits.... I've been chasing the sound for the last two summers with no luck..... sounds like it's sucking air through a bugle, but I can't find where....

 

[BigRedRangerII]

I think I found the problem! I pulled in the garage last night and the sound went off. To avoid taking it out of gear I had the old lady lean over the seat and press the brake so that I could get a good look at the sound.

Sure enough it was coming from the filter box. I plan on looking in there today and seeing if I can't identify the problem.

Does anyone know the anatomy of the filter box on the newer rangers? Thanks!

 

[Bird]

IAC valve is what usually causes the whining / moaning noise in the itake system.


Bird

 

[BigRedRangerII]

Thanks for the idea. I will look into this. Also how would I know if this is the source of the whine? When I pushed on the filter box the sound stopped. fyi...

Also, how should I trouble-shoot this valve? any info is greatly appreciated.

 

[BigRedRangerII]

I changed the IAC Valve. Problem fixed. Thanks.

 

[StepsidePumpkin1998]

Holy cats! Have been having the same problem with mine for YEARS... my mechanic swears he can't "find it". I'm going back to him with this information and see if he can find it now. So glad I found this forum!

 

[cvar]

Yeah, mine had that same whining moose sound, for months. The IAC valve has a round black plastic cap with felt inside. I changed the felt, but that didn't help. Changing the figure-8 shaped gasket underneath didn't help either. Nor did using cleaning solvent inside.

Replacing the whole IAC valve solved it. 2 bolts & 1 electrical connector, and you're all done in under 10 minutes. Then peace..... ohhhmmmmmm.

 

[Dune Runner]

Mine makes a whirring noise when it's hot out and I get stuck in traffic. The fan clutch is the culprit.