I've got a '96 F-150, 5.0 with 116k on the clock. When I first start my truck in very cold weather, there's a fairly loud howl coming from the engine bay that I can't seem to locate. When it warms up that goes away. Then it seems after it's been run, and if it cools down again somewhat, the next time it idles in the cold it will make an intermittent squeaking sound.

Belt is in good shape, and I can't really see anything wrong with any pulley misalignment or anything anywhere. Thoughts?

 

Been there, done that, heres the thread...

http://66.179.14.118/forums/showthre...hreadid=142284

 

Everyone who posted in that thread experiencing the problem had a '97+ truck with a mod motor. Does that mean my power steering pump is the same as theirs and it's still normal?


The moan (sounds like a train whistle) is also intermittent, not something I really heard described in that thread.

Finally, what about the squeaking? Two different noises I know for sure. In fact I can drive my truck around and then leave it idling when cold and it will make the squeaking sound, with the engine warm. Not indicative of a power steering pump noise I wouldn't think, since the fluid should have been warmed and the noise is different.

I appreciate the input, just trying to sort this out. Seems like it's been getting more common so I want to find out what it is quick to avoid problems.

 

tait-gt2002,

We did a lot of joking on that other thread. Your problem does sound like it is coming from a different source, if you can pull the belt off grab a good hold on the water pump pulley and give it some up-down and side-to-side pulls and check for shaft play, sort of sounds like a bad water pump. You really should not feel any play in the shaft. Most of the time when they get that bad they leak water/antifreeze.

T-man

The steering pump noise we were talking about is something that I can say happens to most all (not just late model F-150's) vehicles when they set out in the cold all night and just sounds off for the first minute or so until the fluid gets moving and warms up a-bit

 

Sure don't have any coolant leakage but I will check for shaft play.

As far as the PSP... My Mustang, our Yukon, my dad's F450, his '72 and '73 F150, and our Liberty don't have that whine... I've started about every one of those vehicles save the Liberty in sub zero weather and don't hear anything like on my truck.

My truck also has electrical gremlins that need sorting out but that's for another thread...


BTW, I'm not trying to discredit anything you guys are saying, you may very well be right, it's just that I have two distinctly different noises and neither one matches exactly (or closely enough) to the noises for me to feel comfortable letting it go... Just looking for more suggestions. I really appreciate the help!

 

Some of the good things in that thread describe using the process of elimination to find the source of the noise. Several of the individuals gave some good suggestions to identify the source of the noise although some require more work than others.

An easy one was to turn the wheels after starting the engine (if the noise is a whine) to see if it might have something to do with the power steering pump. Turning the wheels should make the power steering whine vary.

Removing the belt takes more time but can eliminate the power steering pump, alternator, air conditioner and belt. (so if turning the wheels does not make the sound vary but removing the belt makes the sound go away, then the sound must be the alternator, air conditioner or belt and so on and so forth...

Sometimes the dense cold air can make whistling noises in the air intake that you would not hear in warmer temperatures.

 

Thanks, I caught the process of elimination thing but I figure it could be any number of accessories, and pulling the belt doesn't do much to tell you which one is responsible... Is there a way to short-belt certain accessories out of the way that you know of? Thanks.

 

electical gremlins----hate those little devils....

but that does raise a red flag for one more thing to check. Grab that pulley also and check for bearing play. Could also remove the output cable from the altenator and start the truck to see if the noise goes away. Remember that cable is hot to ground, so remove the ground cable from the battery while your removing the altenator lead, and tape the end so it can not short to ground while your running the engine to check for the noise.

Still hear a lot more than not power steering pump whine on those -10 degree mornings

T-man

 

Yes, it has electrical gremlins because I'm an electrical idiot. I did follow what you said just fine, but I guess I am clueless as to what that might do to stop the noise? Thanks.

 

Sorry!

Try unhooking the altenator to see if the noise goes away. Altenator has bearings on the shaft, and if they get worn this puts the center (rotating part) a little off center and can produce noise and or spasmatic output voltage. This could be home for the gremlins also! But not knowing what problems they are causing may or may not be related to the noise.

Unloading the output of the altenator is a check. Noise goes away! Then 86 the altenator!

T-man

 

Me too. I turned the wheels one morning and did not hear any variance in the sound so I think the alternator whined for a bit.

Other than that, it purrs like a kitten in cold weather and starts after a couple of seconds of turning and I am thankful for that.

 

Hey Temp 1

I think an altenator can normally whine a little on very cold mornings, they hate getting out of bed too!

But really I think 2002's problem is more related to a bearing problem (don't know yet just were) he says words like: howl and squeak, these are not the normal cold mornings sounds that I've ever heard. Of coarse sounds are in the ear of the beholder. Sure wish he could record and post the noise, that would be cool. No pun intended. It's already up to -2 here this morning.

T-man I think that's the cold air turning his breath blue!

 

Yeah, if I was home I would be able to actually get a vid with some sound of the problem. No camera with me at school though. I don't have any charging problems with my alternator but I do occassionally notice output fluctuations when looking at the gauge... One time while in for some repairs I mentioned it and the Ford boys couldn't duplicate the problem.

Nor could they duplicate my temp gauge going wild. It never leaves the 'normal' range but spans between it sometimes while driving. I figured maybe it was a gauge problem but who knows. It started a couple years ago, after I romped on it... I layed into the gas until like 80 and the temp needle started bouncing around.

This truck has all sorts of little issues, but all I know is it starts every time and is reliable.

 

The truck I just bought has 2 of your same problems. The Howl you speak of. It is like a tea pot whistle almost. It does it at idle, and if you step on the gas, it changes pitch a little, and then goes away.

And My truck also does the fluctuating temp guage thing. Does it in exactly the same way.

I'm convinced we have the same two problems. My truck is also a 96 with the 302. Did you resolve your problems yet. What was the issue?!

 

I have the same kind of thing - a kind of whistling moaning noise - it seems like it starts with a low pitch and continues to get higher until it stops. it only happens if it's really cold outside - and mostly in the first 20 minutes of driving time although it can happen later if I keep on driving. It only happens at start up or when I'm sort of coasting along or in a low speed pickup - if I"m out on the highway running harder or speeding up from a stop light fast, it's less likely to do it than if I'm just rolling along the street hardly pushing on the gas to keep moving along. It only happens when it's cold out though - - i have 200K and have nEVER heard this unless it's cold - and I've been hearing it since about 50K miles - just never figured out what it was and since everything keeps working haven't worried much about it - but would love to know what it was because it always makes me think I'm going to break down on some backroad in the cold! 2002 F150 Supercrew 4.6 liter V8 tritan motor.