I posted this question a while back, I still haven't figured out what it is, so I'm gonna ask again in hopes someone might be have an idea:

From about 2200 to 2700 RPM, either when I press on the gas or let off, even if very lightly, I can hear a very high pitched whistling sound. If I hold the pedal at the right spot, the whistling sound stays constant until I pass that RPM range.

This sound is barely noticeable with the stock air intake set up, but with the PSP filter kit, it's as loud as squeaky brakes, at least from the inside. The blower is also louder so I don't know if these two sounds are related.

So I've been thinking it's just some kind of effect with the air movement, but I'm not sure as I was driving with my friend yesterday and he said it doesn't sound normal.

Any ideas on what it might be?

Thanks,
Mike

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99.5 Black Lightning
PowerSurge Cone Filter
JBA Jet-Hot coated headers
Flowmaster muffler

 

Some wild guesses, but here goes....

Could it possibly be a bearing in the blower drive shaft housing? Getting some harmonics at a particular RPM?

Possibly a tensioner pulley bearing or cap (possibly similar to Sal's description earlier?)?

Is there any evedince of paint wear on the blower pulleys above the normal travel, like along the top of the guide channel?

Just some WAGS.....


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Chuck 'Wyldman' Shelton
wyldman@houston.rr.com
Black 99.5 Lightning Build # 1273, DOB 5-14-99
CD Changer; Tow Pkg.; Lojack; Sal's custom nitrous chip; G-Tech/Pro; SnugLid; BedRug; Invinca-Shield, full kit; NOS KIT 80 hp shot (currently); Clear and smoke Lexan fog light covers; 3M Ti Window Tint; Bel radar detector (shouldn't be an accessory); PowerStack cone filter (a.k.a. supercharger waker upper); American Auto Designs ram air hood - Delivered and at the body shop; Cal-Tracs traction bars

 

Check your supercharger oil level and look at the by-pass valve for leaks too. Scott

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RED 99 LIGHTNING
CAT BACK FLOWMASTER MUFFLER SYSTEM


[This message has been edited by SCOTTODOG (edited 11-12-1999).]

 

Thanks for the guesses . . .

I called Eaton directly and the tech says it might be the bearing, as Wyldman suggested. How hard is that to fix?

But I also see a lot of paint wear along the guide channels of the blower pulley . . .

I'm going to have to put the stock air box back on (again), and take it into the dealer on Monday. Problem is it's not as obvious of a sound without the PSP cone filter, so I hope I don't run into a lazy mechanic that just brushes it off.

I may be able to take it to the Eaton supercharger division as well if Ford says it's nothing, I'll have to check on that.

Thanks for your help guys, if you have any other ideas, let me know. I will definitely relate all of these possiblities to the dealer.

Mike

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99.5 Black Lightning
PowerSurge Cone Filter
JBA Jet-Hot coated headers
Flowmaster muffler

 

Try contacting Magnuson products they service the eaton superchargers for eaton. HTTP://www.magnuson-products.com/
Have ford get you a new one under warranty.
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RED 99 LIGHTNING
CAT BACK FLOWMASTER MUFFLER SYSTEM


[This message has been edited by SCOTTODOG (edited 11-12-1999).]

[This message has been edited by SCOTTODOG (edited 11-12-1999).]

 

Hey Mike, Sal here. One thing for you to check before you go back to Ford. Check to make sure the IAT sensor is seated shugly against the intake duct on your PSP filter kit. On my prototype one, the IAT didn't fit quite snug, and I heard a similar noise until I put on a bit thicker O-ring on the IAT to make it seal better. The production kits SHOULDN'T have that problem, but you never know. Just figured I'd pass along that tip before you go too crazy

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SAL
13.35@103mph
All stock with PSP 99 Lightning Chip and Filter Kit

Power Surge Performance--- Your SOURCE for SVT Lightning EFI Tuning and Performance!! http://members.aol.com/NLOCsvt/svt.html

 

Well, this weekend I removed the PSP filter to prepare to bring the truck into the dealer today. The whole weekend I drove around and could not hear that whistling sound at any reasonably audible level with the stock filter box. But I decided to take it into Ford anyways to have them check it out, also I needed to fix that clunking sound when I u-turn.

After running some diagnostics and taking the truck for a drive, the Ford mechanics could not find anything wrong. I have to admit, I would not even suspect a problem just driving around with the stock air box. There is no performance loss either way.

And last Friday night, Sal was nice enough to spend time with me on line to help me figure out what the problem might be, made adjustments, got back on line, etc, and could not figure out the problem.

So, should I:

1. just accept that it may be air movement, and hope that if it is a problem it will manifest itself before my 36,000 mile warranty?

2. fork out some bucks and take it to a race shop, with the PSP filter, and have them do some diagnostics and testing?

What do you all think?

Thanks for all the help.

Sincerely,
Mike



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99.5 Black Lightning
PowerSurge Cone Filter
JBA Jet-Hot coated headers
Flowmaster muffler

 

I know this might sound stupid,when I tested my L.at 2500-2900rpm.I can for sure hear a high pitch whistle.To me, my sound's nothing more than high vac.past the thottle blades at this rpm range.Sorry no real help,but maybe peace of mind.

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JIGAWATT SVT#2698


[This message has been edited by JIGAWATT (edited 11-15-1999).]

 

hey brimstone, I think that what you are hearing is actualy the blower itself. I'll bet that if you look at your boost it is porbably just under 0 vacuum with the tach around 2500 when this happens. Well to let you know that is the exact sound that I am getting, if so there is no problem that sound is just like what a regular supercharger sounds like (not the roots style), like a vortech but they are much louder. It is like a high pitched whistle, to tell you the truth I wish mine was louder!!!(hopefully with sals filter it will be) cuz i love the sound of a blower, I wish ours sounded more like a vortech's whistle than just a moonson under the hood, it would defiantly get more attetion from other cars as we blow by them

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99' Black Bolt
Clear Corner lenses
PSP Filter (on order)
SVT #3443


[This message has been edited by Yoda (edited 11-18-1999).]

 

Hey Yoda,

Just wait until you install Sal's filter kit! The sound is unbelievable!!! It still just howls at low rpm's but when you let the hammer down, it literally SCREAMS!

Later,

Collin

P. S. I too have the whistling sound, but the blower drowns it out.

[This message has been edited by Collin (edited 11-18-1999).]

 

Hey guys,

Thanks for all the input, I do feel much better now and maybe a little stupid too if it is just normal blower noise. Yoda you are exactly right, it comes on with boost just below 0 vacuum from 2200-2900 rpm, and there's definitely no performance loss But I would never have noticed the sound without Sal's filter - boy do I get attention when accelerating past other cars. I was watching an autocross the other day and could've sworn I heard the same exact sound coming from another car. I also saw a Mustang GT beat a Porsche by shear brute power. Okay, now I can go back to driving and enjoying rather than driving and worrying all the time.

Mike

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99.5 Black Lightning
PowerSurge Cone Filter
JBA Jet-Hot coated headers
Flowmaster muffler
Lo-Jack