eng208

Hey, I have a question about a noise my truck makes. I always thought it was just the diaphragm on the wastegate, but now I am not sure. When I put the pedal down and boost builds to about 28PSI, I get a fluttering sound that sounds like a rubber diaphragm opening and springing back too. That is why I though it might be the wastegate. It is coming from the passenger side firewall area. But I never see anyone else mention this on here. I do have the #8 TST plate with the elbow, and it will hold boost at 34-35 PSI. What do you guys think? The truck runs good, but this is starting to worry me.
Chris

eng208

Well, I put about 28PSI on the wastegate hose and heard a metallic sound of the valve on the turbo opening and closing when I released the pressure on it. So, I think that is what I am hearing, as the pressure builds rapidly, I get an opening of the gate, followed by a slamming of the gate when the pressure drops off, then opening and closing rapidly, giving me the sound I am hearing. It mainly does it when the boost jumps rapidly, not so much when it builds gradually.
Does this make any sense? I cannot believe that it has been almost 12 hours and noone has replied to this yet.
Anyone have ideas?
Chris

plow

chris, disable your wastgate at the afc. then drive the truck and see if your noise is still there, that will tell you if its the wastegate. If you have the elbow on there it should limit your wastegate to how ever much boost you want, your wastegate should not release until your desired boost pressure is hit. You may have a weak spring or bad wastegate. Personnally I would just disable it and forget about it.