Hi just wondering if anyone can help :

Corsa Vxr 57 plate

My spanner light was showing up recently and the code was saying to replace map sensor which I did with a genuine one. Couple of days later spanner light pops up again with a different code saying "turbo charger bypass valve" so I got the valve replaced & what would you have guessed ? the spanner light is back on !! ... Checked the code again and still coming up with the same code. I've checked all hoses and vacume and all fine.

So i took the car to Vauxhall Garage and they said that i would need to pay £60 for a diagnose to find out the problem but won't it just come up with the same code as i already got? Don't want to be ripped off! I was also told that there are two Valves, one that the back and one at the front and the front was the one that i changed.

Any ideas ?
Thanks in advance.