2002 Astra 2.2 cabriolet. Timing fault baffling mechanics

[Chris Cally]

I have had my Astra in and out the garage for months now.   
fault: intermittent driving and it feels as if it’s bad fuel or fuel not getting through. 
go into 1st gear and the acceleration feels as if it’s chugs as I drive. Go into 2nd ok for minute then same problem.  
had timing chain changed/spark/new Cat also. plugs/valves all done.  
They tested the fuel pressure and it was fine they said. 
Engine management light comes up every 2 wks or so.  The code is related to camshaft position.  Picking car up again today and they can’t pin this down. The mechanics say they have tried everything.  
anyone had similar weird problems. Or can enlighten me on an option for the problem. 
 

Thank you for any input. I don’t  want to get rid of my car, unless I have too. 

[Vauxhall Owners Club]

Have you any update on the car problems ?