Fluctuating boost at WOT

[JohnP]

how big was the gap? i\'ve just looked at mine and i think i have a small split right next to where it bolts down on the seam. its no more than 4mm long, and doesnt cause much problem on low boost. open it up, and it goes really hesitent above 5k. i\'ve already replaced plugs aswell

[Wombat-007]

how big was the gap? i\'ve just looked at mine and i think i have a small split right next to where it bolts down on the seam. its no more than 4mm long, and doesnt cause much problem on low boost. open it up, and it goes really hesitent above 5k. i\'ve already replaced plugs aswell

I have a similar problem, but only when the engine has been running for about 20 mins. I presume it\'s due to the heat softening things up a bit and therefore any hole that may be present opening up.
 
Problem is, I\'m yet to find where the leak is! but hope this is the same issue you guy\'s have experienced.

[JohnP]

to go with this i\'ve been busy posting in another thread, looks like it could also be caused by a sticky CRV (charge release valve - second one back standing in front of the car). as the engine gets hot, i wonder if the valve doesnt operate as well as when its cold? or a solenoid becomes stiff or something..
 
wouldnt mind knowing someone local right now so i could go through it right now (northamptonshire)

[Wombat-007]

I can see now why some go down the single turbo route to simplify things (as well as more power).
All these pipes/valves etc really complicate things. Until I have the cash to go down the single route, looks like I\'ll be under the bonnet for a few hours on Sun trying to figure things out :confused:
Will keep you posted if I find any other cause.