870 that whistles

[Zapah]

I have an 05 870 that when the turbo begins to make any boost over 5-6 psi. Starts to whistle in a different tone than the boost of the turbo. Changed the exhaust manifold gaskets. #2 and #5 were blown out. Replaced now not leaking. Checked and changed the cold side boost tubes. Found a bone needle sized hole. Changed the egr bello.gaskets and new clamps …. Still have this what sounds like a boost leak. ??? Checked the hot and cold side with soapy water found the hot side had small leak. Adjusted them. Solved that. Still have that blowing noise once the boost rolls in?? I’m stumped Thanks

[tree98]

Block off both sides of the turbo, then put 35 psi of regulated shop air in through the cold side(clean air intake side) that will show you if there are any leaks.

Is this 870 still mandated? If it is, how much max boost will it make? If it's making above 40+ pounds of boost, that indicates a bad EGR valve & over-boosting. If it is demandated who did the programming?

[hhow55]

(12-18-2023 )Zapah Wrote:  I have an 05 870 that when the turbo begins to make any boost over 5-6 psi. Starts to whistle in a different tone than the boost of the turbo. Changed the exhaust manifold gaskets. #2 and #5 were blown out. Replaced now not leaking. Checked and changed the cold side boost tubes. Found a bone needle sized hole. Changed the egr bello.gaskets and new clamps …. Still have this what sounds like a boost leak. ??? Checked the hot and cold side with soapy water found the hot side had small leak. Adjusted them. Solved that. Still have that blowing noise once the boost rolls in?? I’m stumped Thanks

I once had a whistling noise like you describe.......And it turned out to be a loose bolt on top of the the egr valve.

[marek4792]

Egr tube on the back of the block, everyone seems to miss that one..

[PolishHammer]

some heavy soap and water on that engine will find the leak, Just try to do it on the cold start up afte the air pressure has turned the fan off.

[Zapah]

Okay hope everyone has a better 2024 than 23. A thank you to all the members who had suggestions on The problem. The problem turned out to be a burned out egr cooler to tube hose…. When he hose burned away. The clamp lost its grip. Blew the hose off the pipe. Every thing has been cleaned up. Adjusted properly for fit and finish. Back on the road quiet and getting the job done. Again thanks to all those who had suggestions. All valuable tips. Happy New Year to Rawze and one and all.

[Rawze]

Thanks for the follow up. I am sure it will help others in the future.

[Benjamin9669]

Watch out for the tube on the back of the engine that one goes frequently, and also the one on the drivers side where that tube goes around.