Astra J gtc 1.7cdti P0299 fault code

[DomRhodes]

Engine light came on went into limp mode  came up with p0299 checked map sensor was fifthly clean it didn't make no difference brought new map sensor worked for 10 mins went back into limp mode with same fault checked air filter incase was dirty no issues there so was thinking might be gas waste exhaust valve.. anyone got any other idea's on issue .. thanks 

[Vauxhall Owners Club]

I would put money on it being the turbocharger variable vanes sticking due to excessive carbon deposits

Try using a cleaner to remove the carbon - links below:
Wynns
JLM
Revive