hello guys, it has been a while since i have posted on here. about a month ago my turbo is making a funny noise for about 10 min when you first start the truck. at idle sounds fine. starts making this noise at 10-15 lbs of boost. it is kinda a wine/ whistle noise. after you run for about 10 mins it goes back to a normal whistle. i have pulled the intake and checked the shaft for free play. i find nothing. turns very freely. any suggestions?

 

Exhaust Back Pressure Valve... If I had to guess.

 

My bet is a boost leak. You can build a boost leak detector for less than a starbucks and find out easily. The crappy worm-drive clamps at the spider and the heads are common culprits. I used to tighten these on a regular basis until I got plenum inserts from Riffraff and upgraded to better clamps.

3" PVC cap drilled and tapped for a schrader valve:


Put 15-20psi into the intake and spray soapy water at all boot connections, plenums, etc.


Let us know what ya figure out!!!!

 

If it was a boost leak would it go away when it warmed up?

 

Nope, but it could easily make less noise when the boot softens up.

Besides, there is no turbo failure mode I'm aware of with your symptoms...

You could just try to tighten the clamps (especially on the bottom of the spider) and report back to us!

Use a bright light and LOOK at all the boots, ya may just see the problem.

 

Exhaust Back Pressure Valve... Check it...