02' 7.3L diesel with less than 65k miles on it 100% stock. Owned since new.

Here is the situation:
When accelerating with a loaded trailer or a load on it (but not always) I get a whistle/chirping sound randomly. It is not steady but wobbly. Accelerating more does not intensify the whistle or change it's tone... it's just there. I can drop back to an idle, then go again and it clears up.
No code has ever been recorded because of it.
The truck has less power while it is occuring.
It has done this since new but has become more frequent and more frequent when it is not loaded.
It's done it minutes after starting and after hours of running.
I've never been able to demonstrate it to a mechanic and despite describing it and having it looked at by ford more than a dozen times, I keep getting NPF on that part of the ticket.
The engine appears fine, the power is good (while not whistling), nothing seems amiss.
It is more of a nuisance, I'm about to take a 2000 mile round trip towing about 8000 lbs and I expect it to occur about 6 times during the trip. Of course, it generally occurs right when I need the power, like passing or merging into traffic etc...

So... I still have engine warranty and I'm bound and determined to figure out what this is and fix/have it fixed.

Can someone suggest what might be the problem and maybe give me some diagnostics process I could use to find it and point at it so it can be fixed?

I'd considered getting a diablo tuner because I see it reads codes and shows live data while driving.

Comments, Ideas?

Thanks,
Robert

 

that is called turbo surge..it is not good for the turbo..drop a gear or let off the throttle a little..this can be fixed with a wicked wheel or the ATS turbo housing

 

you can get the wicked wheel here

http://www.dieselsite.com/index.asp?...PROD&ProdID=47

and the ATS housing here
http://www.dieselsite.com/index.asp?...ROD&ProdID=479

this is not the only site that carries these..there are many of our sponsors that sells them..how ever Bob is a great guy to buy from..very helpfull and gets your orders right out..

 

I'm not sure how I could be getting turbo surge at less than 2000 RPM in an unloaded truck. This chirppy whistle can start with even slight acceleration, it will remain until I relent and give it an idle. I can pour on the power or back off the thottle, still there. I can ease off the throttle so I know the turbo is "relaxed" but not idle, even start to decelerate and the whistle will fade a little but when I start going again it's back. Only a complete removal of the foot from the pedal so it idles then return to normal operation gets rid of it. Then I can pull like as hard as I want without a problem.

I'd thought maybe something involving the bypass or waste gate may be involved, but don't know how to demonstrate it or localize it.

Robert

 

hmmm must be a boost leak some place..check all your boots and clamps..may need to take the boots off clean the oil off of them with dawn dish soap,clean pipes check boots for cracks and holes.. put it back together and tighten clamps good...also pull the intake tube off of the turbo..grab the nut on the wheel..try to move it up and down..side to side..then in and out..there should be no play on that wheel at all

 

I am bringing this thread back from the dead my completely stock 01 auto with 75,000 mi has the same identical chirping under the same conditions. I am gonna pull the turbo inlet hose tomorrow to check for dusting and excessive play. If it is the turbo what is the best way out of this mess?

 

Replace or rebuild the turbo, and replace the poorly designed stock air box a good intake (6637, AIS, AFE, etc. Just not K&N).

 

I never really did solve this issue either. I see no leaks etc... and I've just been ignoring it. So I'd like to know what you find too.

 

harry --> it's very hard to make guesses at what's going on with your truck because it's up to us to imagine what it sounds like. If it's chirpy, as in short burst "chirp-chirp-chirp" sound, that's classic surge description. Or, as Ron said, the wheel could be hitting the housing. But there is some (and I mean very little) side-to-side play allowed. But no in-and-out play. If you can move it enough to hit the housing, then clearly that's the problem. In that case, stop driving it before something breaks off and it gets really expensive.

 

Harryball42 what have you tried so far?

 

I did not get a chance to check mine today, I am thinking it's probably dusted I ran a k&n for 5 years before this. I will keep everyone posted.

 

I forgot one other thing is turbo surge kind of like the big pulling trucks when they let off the gas and you hear that turbo blow off a couple of times. Like I said mine does not do it all the time it kind of comes and goes.

 

Here's what surge sounds like (pay attention right around 14-16 seconds into the vid):
http://rides.webshots.com/video/3014889180054835005EcZsHk?vhost=rides

Mine surged at the very top of the boost curve, so it made more of a pst-pst-pst sound.

 

Also since you say it is chirping, double check your idler pulley, and fan clutch.

 

This will not cause a loss of power.