When driving my van i'm noticing a strange sound when at the higher end of the rev range, it sounds like its coming from the turbo. The noise sounds like air being released from some where. But it doesn't sound like healthy air release, it sounds tinny and rattly, hard to explain with words.
When this noise occurs the van loses a little power, which makes me think its the turbo.
It happens in all gears at high revs, when in 5th gear the noise will occur for a second or two with a little power loss, the noise then disappears for a second or two van surges forwards a little, the noise occurs again for a second or two van loses power so on and so forth.
I've tried revving the engine by hand from the engine bay but don't hear the noise.
Any ideas what it could be.
Engine has just been rebuilt, but the turbo hasn't.
Any advice greatly appreciated.
