Gotcha on the wind noise part. But the fact still remains that when you push the clutch pedal down, the noise goes away. Can you get the noise at all with the clutch pedal pushed down? Is it a constant squeal, or does it change pitch with vehicle speed, or engine speed?

 

The noise doesn't change in pitch and is always the same. If in 2nd gear at 2800 RPM the noise is present. If I reduce RPM with the accelerator the noise is still present until 2500 RPM, then disappears below that RPM. If in the garage I can push the clutch in and increase the RPM to 2500 and get the noise, disengage the clutch and still have the noise until I reduce the RPM below 2500.

 

I think I am missing something here. Now you are saying that the clutch has no effect on the noise??? Remove the serpentine belt then see if the noise is still there.

 

HOLY CRAP!! I have the same EXACT noise!! For me it happens between 2000 and 2500 RPM and I have an automatic. It just started happening a few days ago. Sounds like a tea kettle when it is just starting to whistle. Low pitched wirbly noise. Doesn't matter what temp, whether AC/heat is on or off, whether driving or parked. Same RPM every time.

I pulled apart the cowl under the wipers and found nothing. I popped the plastic cover in the center of the dash and found nothing. The sound is coming from in front of the dash behind the defrost vents.

i'm thinking there must be a small leak between the engine compartment and dashboard. The engine will produce a certain velocity of air towards the back of the engine compartment that probably would not be affected by the wind of driving since it is up high inside the engine compartment. Now the trick is finding it and sealing it!!

PLEASE TELL ME IF YOU FIND OUT WHAT IT IS and I'll do the same for you.

 

Do you think that there is any possibility that the tachometer is the culpret?

 

Hmmm.. You know.. That's something I didn't think of, since it is RPM related and is coming from the dash. I don't see how though as the tach is electronic. It's not like the old cable driven speedometers. Something to keep in mind though.

 

I agree with you, and the noise doesn't seem to be coming form that location, but might be worth a look.

 

problem solved. The whistling was coming from the heater hose. Ford was having problems with heater cores prematurely failing in 98 to 03 F-150s so they installed a restricter in the heater hose that goes from the engine to the heater core inlet. The restrictor is closest to the engine block and can easily be identified by a second clip just about the clamp that holds the hose on to the engine. I removed the restrictor and the noise stops. Now I'm just wondering if my heater core will fail because of this..

 

If the restrictor was used to decrease the volumetric flow rate of coolant through the heater core, then there is the possibility that the unrestricted flow rate will cause excess erosion which leads to heater core failure.

 

Had a local shop replace both heater hoses and the noise is gone. Thanks Etch for all of the insite.

 

No problem. Glad the noise is gone. I know it's a relief. Did they put regular hoses without the restrictor in?

What about your temp control problem.. is that fixed too?

 

I rolled the dice and took a chance on an oem hose, seems to be working fine, hopefully it was a bad flow restrictor in the old one. The reason that I changed the hose is that my AC compressor went south; $1500 later AC works fine and all hoses replaced. Although still no temp control with the heater

 

Did the OEM hose come with the restrictor? If so, I may order one. I dont' have the noise anymore, but the point of the restrictor was to extend the life of the heater core.

 

The new owm hose had the flow restrictor