extremely high pitched noise

2002_lincolnLS

2002_lincolnLS

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So fantastically enough my arguably reliable LS is making a noise. It is a high pitched whine from under the hood started yesterday.

Car Info
123,000 miles
2002 V8 Sport
Newer Coils all around
Newer MAF
Newer Degas
Spectre Air filter and adapter

Yesterday when I started the car it popped then the whine occurred.

It changes pitch with engine speed, but not necessarily is it 100% responsive to engine speed, meaning it won't change immediately when revving the engine, but will sort of catch up to the change.

Also it does it while sitting still, so wheel bearings, brakes and the likes are out.

Anyone ever have this sort of issue, I haven't had a chance to check it out as yesterday it sounded like it was coming from the speakers, but this morning I started the car and got out to go back inside and could hear it coming from the motor, or at least under the hood.

Plan to scan it here a little later this morning.
 
Last edited:
2002_lincolnLS said:
...Yesterday when I started the car it popped then the whine occurred.

It changes pitch with engine speed, but not necessarily is it 100% responsive to engine speed, meaning it won't change immediately when revving the engine, but will sort of catch up to the change...
Click to expand...

I going to guess a vacuum leak from the symptoms...
 
I was kind of thing cracking intake tube or the likes (some sort of vacuum leak)

It is lean on both banks and no low fluids so I know it wasn't a fluid line of some sort.

I will try to take a better look after work.
 
start with all the pulleys, IF you think you found it.. pop the belt off and spin by hand (if you can) my money's alt or tensioner pulley
 
interesting update.

Last night on the highway I decided to drop it into 4th to see if the noise changed with RPM, it did not, it only changes when I press or release the gas pedal. So I am thinking against pulleys as it does not actually change with engine speed, but with throttle position instead. Looking like vacuum.

Also the sound does not change when pressing brakes, which I thought it would if vacuum since the brakes use vacuum, however I am not sure how each line is effected if directly or indirectly by the use of the brakes.

Also at about 2200 RPM at high way speeds my vacuum gauge says 22hg and it is tapped into the line that goes into the manifold behind the TB on the front, not the small one from the fuel pressure sensor but the other one.
 
That is what I am going to look for tonight, got a can of starter fluid hoping to find a crack, this noise is driving me insane.

It is like listing to nails on a chalkboard everytime I'm in the car
 
That is definitely an intake leak, and I'll bet it'll be right next to the throttle body if changing the throttle affects it that much. It won't be a large leak if it's high pitched either. Try whistling, your lips make a larger hole for lower pitches and a smaller hole for higher pitches. The brakes wouldn't be affected either because one, the size of hole needed to whistle is too small to cost much vacuum and two, the vacuum booster is a vacuum accumulator. It'll accumulate a lot of vacuum under high vacuum situations, then a check valve keeps it from escaping.

While looking, also check all the small vacuum lines. They can look perfectly fine, but when you touch them they fall off or crumble.
 
A friend let me use his heated garage last night to look at the problem.

It turned out to be one of the vacuum lines that go into the thing bolted to the driver side strut tower (not sure what that is called)

The tabs that hold it on over the barb cracked off and it was able to slide off the fitting. I pushed it back on and used a zip tie to keep it tight on the module until I can find the part number and get a new line. No more noise.

Also the elbow on the fuel pressure sensor was deteriorated so I replaced that. All other hoses are in good shape as I replace them and the and any connectors and elbows I could last summer. This is the third or fourth time I have replaced the fuel sensor elbow, they seem to split much more often than others.
 
2002_lincolnLS said:
...It turned out to be one of the vacuum lines that go into the thing bolted to the driver side strut tower (not sure what that is called)...
Click to expand...

First off, that is not really a strut tower, as the LS does not have struts. (Yes, there is a difference between struts and coil-over-shock. Even through all the parts catalogs call them struts.)

That thing is called the evaporative emission canister purge valve. It feeds the gasoline fumes from the carbon canister back into the engine.
 
joegr said:
First off, that is not really a strut tower, as the LS does not have struts. (Yes, there is a difference between struts and coil-over-shock. Even through all the parts catalogs call them struts.)

That's thing is called the evaporative emission canister purge valve. It feeds the gasoline fumes from the carbon canister back into the engine.
Click to expand...

what he said
 
oh man it's on a STRUT Tower

The EVAP canister purge valve:

is normally closed.
regulates purging of the EVAP canister.
is controlled by the PCM.
is located in the engine compartment on the LH strut tower.

just giving you a hard time,;) I understand the difference, however I would find there to be less difference in a strut vs shock tower other than the adjustability of the strut tower (caster and such)

At any rate, it's semi fixed, now to see if I can find the replacement plastic hose or use a rubber hose with worm or spring clamps if I can't get the part.
 
Remove the accessory belt and see if it still makes that sound. It kinda sounds like a dry pump noise to me, but I don't hear well and don't do too well at diagnosing by sound. Could also be a dry bearing getting ready to go, from the BB in a tin can sound when you hit the gas. Good luck, wish I could provide better help.
 
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