Turbo (?) hissing at medium to high rmp's

[Nero]

Hiya. I'm hoping someone here can help me track down a problem with my 98 2500, turbo diesel (5.9 litre).

It starts fine, idols smooth, and seems to be perfectly normal during exceleration in 1st and 2nd gears. In all gears above 3rd however, there's a hissing sound that begins at about 1800 rpm, and I don't seem to get benefit from the turbo. I used to feel the customary "umph" as the turbo kicked in, and that's no longer the case.

It seems to happen most if I'm trying to excelerate quickly or if it's under load (towing). It will continue to hiss in 5th until I've reached a stable speed and ease back on the excelerator. And even then it seems as though it's still there to a certain degree, although very faint.

In all other aspects it seems to be fine. No over-heating. No stuttering. No noticeable lack of power (except when the turbo should be giving a boost).

If this is related to an air leak somewhere in the turbo, how may I pinpoint it while searching at idol? If it's not related to the turbo, why would it only occur when the turbo should be kicking in?

Any help would be greatly appreciated.

Thanks !

Nero

[Backyard Mechanic]

Check all your rubber connections between turbo, intercooler, and intake. These rubber boots do come loose from time to time. You should find a loose clamp or maybe a torn boot.

[conmeecowboy]

if you have not found a loose hose take it to your dealer or a heavy truck dealer and have them pressure test the charge air system that will tell if your intercooler or one of your hoses are leaking. it doesnt take long and will pinpoint the leak. good luck.

[conmeecowboy]

sorry i should have mentiond this with other post but if your intercooler is leaking take it to a good welding shop that welds aluminium and see if they can fix it. it will be a lot cheaper than buying a new one.

[moparboy99]

hey

check your waste gate. if it has one witch I pretty sure it dose. that might be bad or the turbo is possible bad. does it smoke under a hard pull?

[TRAILDUSTER79]

I Am A Truck Driver..... Turbos Hiss No Mattoer What You Do Unless They Aren't Being Used....now As For A Dodge Turbo..the Above Are Good Things To Try And Usualy Will Fix It....i Also Have A Dodge Dually Diesel And I Have The Same Thing, Feeling Like No Power....usualy Turbo Has Gone Bad, It Sound Right But It Is Junk. I Have A New One Coming In....hopes That Isn't The Problem, It Gets Expensive...................... Besides, If You Loose The Seal Anywhere In The System, No Power. So Check Everything From The Air Filter (wash It Is Should Be A K&n) To The Intake At The Injection Area.........good Luck