Help: RPM related underhood Whine.

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lseguy

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2002 V8 LSE with 65,000 miles.

Over the past couple of weeks, I have been hearing a very noticeable whine coming from the engine compartment. The whine is directly related to the engine RPM's. The higher the RPM,s the higher in pitch/tone the whine. Everything is working fine...power steering, charging system. Having the AC on or off makes no difference. With the engine running, I placed a long handled screwdriver against the throttle body area and listened via the handle of the screwdriver. Nothing. Placed it against the "pump" type device that sits on the passenger side of the engine compartment. nothing. Placed the screwdriver ontop of the passenger side valve cover...can hear the whine there fairly loudly.

Any ideas what could be the cause of this whine? any other troubleshooting tips?
 
And just to clarify. The whine is intermittent, and at this point, I can't determine any consistent conditions that make it occur.

I do not think it's an alternator type whine, because it is not emanating through the stereo/stereo speakers.

It is not a rear end whine/tire whine, because it occurs at idle..park, neutral, or Drive.
 
It can still be the alternator. Bad bearings in the alternator will not produce noise through your speakers. Even things like bad diodes, regulator, etc can produce noise from the alternator and not be heard through the speakers. They can cause some wierd things to happen electrically inside the alternator that will make noise. If that's the case...your alternator is on it's way out. However, any competent charging system check would see that. But where it's intermittant, I'm betting on the alternator. Remember too...if it's heavily charging, it will make noise and that is not necessarily wrong. Maybe the only time you're hearing it is when the battery is needing a heavy current flow.

Get your long screw driver out and check the alternator, water pump, power steering pump, hydraulic fan pump, all idler bearings and tensioner pulley...everything the belts turn. It has to be one of them.
 
Thanks for the input.

Update...today I turn the car off...then when I went to start it, seemed like it was turning over a bit slower than normal, and took 1 to 2 seconds longer to crank over. To make sure it wasn't my imagination, I re-tried it..same thing. My on board computer indicates "CHARGING SYSTEM OK". But admittedly, I haven't had a chance to put a voltmeter on anything yet.

And I need to add one more symptom that I forgot to put in my original post. The day before I made this post, I hit a small pothole in the road...NOTHING major...then I got the RED warning on the dash along with "CHARGING SYSTEM ERROR" or something of the sort....I pulled over, restarted the car...and the warning/issue never resurfaced.

I'll do more testing and keep this thread updated.
 
One last question....are there any writeups on here for alternator replacement? I did a search, and havent seen anything. I'd like to study in the event it is the alternator going south..
 
Before you go taking the alternator out check to see if you have a hydraulic cooling fan. Mine went out a while ago, the whinning you may be hearing is your fan kicking into high to cool the engine. Do a search on this topic as well, I know there are many posts on this issue because it was a common problem.
 
Thanks...and oh, I did find a post from QuikLS on alternator removal, if it comes to that.

I'll check the fan as well....but Im certain that the whining has occurred when the engine is cold as well as hot. As an example, I went out for lunch today. Car was parked in the underground parking garage for 4 hours before I started it....instant "whine" from under the hood.
 
Update:
On the drive home from work. With Ac running, stereo on..no lights (daytime)...had an ABS and Advancetrac warning while at a stoplight...within 4 seconds, both lights turned off. I turned off the AC, and made it home the rest of the way without incident.
Just went out to the garage. Put a digital meter on the battery. 12.38 volts. Started the car..with no accessories on, and at idle..12.66 volts max.
turned on high beams and AC..and at idle, voltage dropped to 12.16
Also noticed that the "eye" on the battery is no longer green, but Red.

And the whine was present during my garage test above, even at idle.
Alternator and battery?
 
Sidenote....I double checked the onboard computer. "Charging System OK" is still the current message.
 
Maybe it is a bad battery that is pulling all the juice from the alternator, but more likely a bad alternator despite what the computer says.
 
Drove fine today..Took it to AutoZone (or was it Advanced Auto?) and had them put it on their electrical check machine to test the charging system/battery under load.

Battery tested fine, but charging system was under spec. At 2000 rpm, she did put out about 13.4 volts...but as soon as it would drop to idle, it dropped to about 12.6 volts or less. Whine is now constant.

Dealer quoted around $260 or so for an alternator.

Decided to go with this one...Lifetime Warranty. special ordered it this evening, will be in store for pickup tomorrow morning.

http://www.partsamerica.com/Product...LT&mfrpartnumber=P825676G&parttype=11&ptset=A
 
Ouch the alternator is in a bad spot. How hard is it to change in these cars?
 
You telling me it's in a bad spot.

QuickLS..someone..anyone...HELP!

So I followed the directions, and I have both top and lower bolts completely removed from the alternator. Per the directions, it should move freely/twist sideways now, so that I can unplug the wiring harness clip, and unbolt the charging cable.

But this thing is NOT budging. I was able to wedge a screwdriver under the bottom, and Im able to move it approx 1 inch upwards, and then 1 inch downwards. But I am unable to actually free it any further than that. It's not the cable/harness, because I can easily see the free play in those. It's as if the top mount is wedged tightly between the two support "holes" that the bolt goes through. But there is no room to pry anywhere else but from the bottom/side.

Please...what's the trick to getting this thing out of there once the bolts are removed? Im dead in the water right now...
 
Its the alt.



Just get a new alt..

And having alternator whine is NOT something bad. Its still doing its job, and powers your electrical system. most people with after market system get this laternator whine becasue they are over working their alts, but you r alt will survive for a loing time. so if the noise does not bother you just let it be
 
hey since you are replacing the alt buy one that has more load capacity so you are able to expand in the future ..... hey and i have to say that was some good troubleshooting, good job.
 
Sunday Morning Update..

Worked some more last night in the garage to attempt to free the alternator from in between the top mount...no go. If she was up on a lift, I could reach upwards and grab with good force and pull downwards. But laying on my back in cramped quarters is not allowing me to get enough force to free it from the top mount, and there is no room to get a prybar up in there. And looking down from under the hood provides no room to get anything to push downward. So...back together she goes, and in the morning, I will take her to the local Ford dealer to have them install the alternator.
 
I can't remember on the LS, but most Ford's have a bushing in the top mount that tightens up against the alternator when you tighten the bolt. This allows for a good solid mount AND allows for any size variances in the alternator mount, AND...believe it or not, makes the alternator easier to install! You have to pry the alternator back against that bushing to move it...then the damn thing will fall out. I wish I could have got this information to you sooner...sorry.
 
2001 LS8 Sport.

Thanks for the info.

I actually know the bushing you speak of. They are sort of a rust colored metal. There are two..one upper and one lower. Both are on/in the rear mount holes. The lower one is easy enough to push outward..move the alternator as far to the front as possible in the mount..then stick a flathead in there and push outwards..no problem. Plenty of access. But that upper one...there is minimal, if any access. Laying on the garage floor, looking up..I could not find a way to get any tool up in there to push that bushing out at all.

In another thread, someone claimed to have a Pep Boys do a alternator replacement (labor only) for $60.

That's hard for me to believe, with the labor involved. Dealership didn't get to it today (dropped it off late last nite) due to lots of cars from the weekend...but they called and gave me a quote of $220 labor. I could easily call them now and say "no thanks, I'll drop by and pick it up"...but with 100 degree temps in the DC area today...I'll pass on going back under the car.
 
So I just now had the whining and I got the "Check charging system" sign. Is this more than likely the alternator?
 
my whine i had was relayed to a bent hydraulic fan pump pulley. check out your pulley
 
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