My wastegate actuator is likely to be stuck, max boost is 0.5bar and havent found any leaks , and no error codes in ecu, how would I loosen up the actuator or clean it

already cleaned the boost solenoid

its a MY00 with 3" downpipe and 3" exhaust and a 4" backbox , pipercross airfilter and a blitz bov

 

What year and model...Unlikely the actuator itself is jammed as this would generally cause overboost not a lack of...

 

its a MY00 2.0l GT not sure what it would be called in the uk

 

Sounds like limp mode to me, did you do a diagnostics on the car ?

a defect sensor somewhere, could be maf sensor, the diagnostics probably wouldnt tell if it is the maf sensor anyway

 

no sensors show any errors. Air flow meter doesnt show any abnormalies
no symptoms of limp mode other than lack of boost

 

Can you take the turbo heat shield off to see if the actuator is still attatched to the penny arm? Most likely it's came off and you'll need a new circlip.