I just noticed a whistle noise coming from under the hood. It is there at idle and it increases a bit as the RPM goes up. The closest thing I can think of to explain it is it sounds like when you don’t have a good ground on your stereo system and you hear that high pitch whistle (through the speakers) and it gets a bit louder as the RPM goes up. You know the sound?

Do all L's make this noise and I just didn’t notice it before? I could have swore my truck did not make this noise 2 weeks ago. It sounds almost like a turbo whistle. Is it a noise the blower makes?
Note: I am not talking about the whine of the blower. This is a high pitch whistle that is not loud. You have to listen for it to hear it. It definitely changes as the RPM changes. You can hear it when you get hard on the throttle due to the loud motor, exhaust and blower sounds.

Oh and one more question. Are the 2nd Gen L's known to have leaks in the exhaust system? I heard this noise from day one? It is the Pff pfff pffff noise that you hear when you go 1/2 throttle with an exhaust system that has a small leak in it. I hate that noise. Is it just the stock crappy clamps? Is this a known problem?

Thanks guys

 

Did you put a throttle body on recently?? The aftermarket TB's make a quite loud whistling noise.

The exhaust noise has been on every L I've ever been in since my first one back in 99. It's more prominent when the truck is OD and you place just enough load to accelerate but not down shift.

And, I could be full of *****. So if neither of these help, ignore them.

Jason

 

Nope no new TB on the truck but now that you say it I remember people saying this. I wonder if the stock TB makes the same noise?

As for the exhaust.. you are exactly right. You can hear it more when thre motor has load on it but it does not downshift. I am glad to see its not only mine.

I am still curiouse about the whistle noise though.

 

I know the whistle noise your speaking of. I have it too. I noticed it after I put the 6# lower on my truck w/ the gator belt. I believe its the belt or something spinning so fast its causing a whistle. I don't think its anything to worry about.

-Mike

 

Sweet I have the gator belt with a 6# pulley too. I am glad to hear this. I also think you may be right since when I checked it out it made me think the belt or one of the pulleys was making the noise.

Thanks

 

Yup man. I was worried at first too, but after I thought about it... it didn't bother me.

-Mike

 

That noist that sounds like a exhaust leak sounds like the beginning of a spark plug thats about to fart out of the head.Anyone agree????

 

After I added new cold air intake kit, with open air filter and SB throttle body I can hear a high pitched whistle noise when you put a little pressure on the gas, right wehn boost bypass kicks in. I think its the sound of the air being sucked in thru the filter noise.

 

i have the same noises. i notice the whistling noise after putting on filter kit and single blade t/b. so i took everything back off and went back to stock. the noise is still there, so i think maybe it is from the belts. i have stock pulleys and motorcraft belts. the only thing i can see wrong is the two pulleys on each side the paint is starting to come off, so maybe thats causing the noise. i think i'm going to buy next a really loud system so i cant hear anymore noises and get my mind back.

 

The sound is coming from under the truck and was there from day one. I bought the truck new and the sound was there from the second I drove off the lot. I dont htink its the plug in this case and also pray you are wrong

 

Can it still be that even if I have the solinoid (SPL?) unplugged? I did not do the by-pass but rather unplugged the plug.

 

The worse thing I can do is drive with the radio off!! When I do that I hear so many noises and just make myself paranoid. LOL

 

Mine started whistling after I took the stock TB off to clean the oil out of it. Must be something with the gasket.

 

I get paranoid when I turn my radio off at a light and only hear the truck idling..I can't stand hearing skips and even when I have the radio up loud, when i feel a shake I blame it on the beat from a song..

 

Mine has that same whistle...but only after i put the 4#er on. I kinda think it sounds cool