In 4th or 5th gear the car pulls fine upto 0.6 bar on the boost gauge, it then rises to 0.9 but fluctuates back to 0.6 and back up to 0.9 again which as you can imagine causes the car to act as though i'm coming on and off throttle.
It wont hold full boost as it just keeps bouncing up and down.
It has a VTA dump valve fitted but i've checked all connections which are good, any ideas as to what is causing this would be great.

Zippy

 

buy a decent gauge an set it up right like you did for me.....go digital.

 

Try cleanin the boost solenoid

 

Another voted for the wastegate solenoid. Clean the manifold pressure sensor whilst you are at it and the restrictor, which is in the pipe that leaves the tubo body, on the pressurised side.

The 01 has a soft boost cut, inlike the violent cut of the classics, so can give a boost pressure pendulum effect when things aren't right.

 

UPDATE:
I replaced the VTA dump valve back to standard.(No change)
Then i cleaned the boost solenoid and all associated pipes and manifold pressure sensor with brake cleaner.
RESULT:
She's now back to normal,thanks for the replies and advice guys.

Zippy

[Edited by ZIPPY - 5/16/2003 9:52:58 AM]

 

Where about is the boost gauge,cant find it on my car

PS Ive just found out Ive got two trip meters,clever me!

 

My mates was doing the same and it was MAFF sensor changed that and it was perfect. Power Engeneering charge about £100