airplaneman00

I have a high pitch whine happening when my turbo is producing over 5psi boost. the higher the boost, the higher the whine. Nothing like it normally sounds. It just started happening. No driveablilty issues, no low boost, no high egt's, everything looks ok. Any ideas??

Nor_Cal_Angler

similar problem here.....i got no response on the 24v board....

discription is as follows:

periodic higher pitch noise...only when truck has warmed up...usually after an uphill or BOOST heavy (9-15#) run, once i hit the pedal it goes away...let off it comes back...tap the brakes it goes away...sometimes comes back and sometimes doesnt....on a warm day it seems to be more frequent...but still sparatic...

no issues with drivability,making boost production,lack of production, no smoke, and i checked the intake and the wheel isnt oil heavy or bone dry..just your normal build up after id say a three month non-check.

any suggestions would be nice....

a thought is the AC compressor....maybe...i dunno..

thanks

NCA

airplaneman00

this only happens with boost build up. Sitting still nothing, . Whatever it is it is load, and pissing me off. Mine doesnt go away

TxDiesel007

might wanna check

the four 15mm bolts that bolt the turbo to the actual manifold. I have two loose and caused that same howl..

Rick

Stamey

Look for the boost leak. It's probably someplace where there is rubber involved. You ever pull the neck of a balloon flat as you let air out of it? This is the sound when a boost leak starts on a rubber boot or rubber gasket.

Nor_Cal_Angler, you say your noise happens on coast?

Chris

CrashCade

X2 on that. I had a similiar issue, but it was at 35 pounds plus.

Nor_Cal_Angler

yea....it happens on a coast...grade dosent matter.(usually downhill, or like i said after a good spool up) wierd part is it doesnt happen when the motor is cold...like morning, or after a good long park job...only mid day when it is HOT or the engine has been running for a good amount of time and is warm..just did it a little bit ago after driving around town...started at the stop light and cont. all the way home and did it while idleing in front of the house.....

man this is wierd....i am gonna check the bolts just for grins....i am pretty sure it isnt a leak...i checked my intake last night re-tightened hose clamps..

92DuallyCTD

I realize you are referring to an unusual or new whining sound with your truck(and I hope it's something simple..) but do you realize how many of us with the older turbo's would KILL for that whine??!! Least a'ways I would have, before my WH1C housing swap! Now that is suh-weet!! Good luck with it, hope you find the problem soon!
PS
Could a sticking wastegate(closed) possibly cause some pressure buildup behind the compressor wheel and produce a 'whine' instead of 'bark' like the H1C's do? If so, the wg actuator might work freely when cold and stick when warmed up? Just a thought...

airplaneman00

this is a very loud, anooying whine. Very loud in the cab. you have to turn the radio up loud to not here it. It is not a whine like a turbo.

drafalske

Check your left lower intercooler boot. On my 2001, it was in contact with the inner fender and eventually rubbed a hole in the boot. Anything over 20psi and it would scream like a whistling bottle rocket. Had to replace the boot and modify the inner fender with a hammer so they would no longer rub.

TSB

My '96 popped the rt. side boot at the intercooler. The clamp was loose. After I fixed that one I checked the others, they were all loose. Made the same noise you describe except once I got much above 1/2 throttle it started putting out a lot of black smoke.

O-C-D

Ive got the exact noise that stamey brought up with the balloon description at wot, nice loud normal turbo spool and then the balloon chimes in and ruins the whole experience. I still get 40lbs of boost but wish i could get rid of the squeel trying to drown out the turbo. I guess its time to build a boost leak tester since ive already checked all of the clamps and gaskets twice.

Nor_Cal_Angler

my noise isnt so loud that you have to turn the radio up...but when you do hear it...it is louder than the engine and exhaust (straight pipe no muffler)

it is almost like the high pitch sound your brakes make comming to a stop...but i know it isnt that because i got that one as well...time for some new pads...lol
NCA

Remnik

You might want to check out this thread:

https://www.dieseltruckresource.com/...d.php?t=127799

When I had the strange whistling sound it wasn't boost related, but when you say that it only starts when the truck is good and warm it sure sounds like the same issue as my '99.

Nor_Cal_Angler

thanks....printed it off and gonna investigate that...it does fit the bill...it is in the area of where my noise is comming from....but the TSB says mostly heard from inside the cab..."you may need to sit inside the cab to hear the noise"

well i can hear it either way....none the less i will look at it tonight

thanks again

NCA