Unusual Engine Sound

[sdcyclist]

My 2006 36FDDS has started to make an unusual sound when the turbo is spooling up. I noticed it over the weekend coming back from a trip to Borrego Springs. It is a hissing sound that increased as the turbo spooled up--not the usual slight comforting whistle of the Cummins ISL turbo.

Any one have this issue and what was the cause?

sdcyclist

[sdcyclist]

My 2006 36FDDS has started to make an unusual sound when the turbo is spooling up. I noticed it over the weekend coming back from a trip to Borrego Springs. It is a hissing sound that increased as the turbo spooled up--not the usual slight comforting whistle of the Cummins ISL turbo.

Any one have this issue and what was the cause?

sdcyclist

[Old Scout]

My five "guesses:" 1) exhaust leak between turbo and muffler; 2) leak in your inter-cooler radiator[seals can give out/cross tubes can rupture]; 3)leaking exhaust manifold gasket[usually has a pulsing sound based on proximity to one of the cylinders];4)the turbo itself or 5)something totally unrelated to the first four. Sounds like a job for Cummins.

[Ted III]

sdcyclist, I would head directly to Cummins or a very good Coach Care

[swansnest]

sdcyclist -
I would bet that it is a turbo-pressure leak between your turbo and intercooler. Check the inside bend of the blue silicon boot on the left side of the engine coming down from the turbo. (Use a mirror if you need to but you can feel it if you reach around.) They had some defective ones last year.

On our early '07 Apex we had this boot blow out while returning home from Vegas Rally and we lost power. Tris had WRV overnight us a new boot and he replaced it w/o a problem. Just make sure the strap clamps are tight. There is also one on the right side behind the black intake boot - should check it also.

After replacing it our mileage (mpg) even went up & we think it was leaking from the start!

Good luck -