If you suspect that your wastegate is getting stuck open, you will need to check this out. With my down pipe off and the wastegate linkage disconnected, you can move the wastegate lever back and forth. My wastegate valve was getting caught on the top edge of the casting. This is the position that it was getting stuck approximately 30% of the time.
I taped off the hot side of the turbo and proved my theory, no more sticky wastegate valve.
Solution: Round off the edge all the way around on the wastegate valve. I used a Dremel with a sanding disc.
You can see the profile of the bottom edge is rounded off. It used to be a 90* right angle edge but not its rounded off and doesn't catch at all. I moved the flapper valve about 50 times and not one catch.
I hope this helps some of you with your boosted sleds.
I taped off the hot side of the turbo and proved my theory, no more sticky wastegate valve.
Solution: Round off the edge all the way around on the wastegate valve. I used a Dremel with a sanding disc.
You can see the profile of the bottom edge is rounded off. It used to be a 90* right angle edge but not its rounded off and doesn't catch at all. I moved the flapper valve about 50 times and not one catch.
I hope this helps some of you with your boosted sleds.
