2002 Beetle P0507 P0335 P0441

I have a 1600cc 2002 beetle. A couple of weeks after a service (after which the car accelerated much better) got warning lights diagnosed as p0507 (throttle body) , p0335 (Crank position sensor), p0441 (Evap valve). Garage wants £1000 to replace these parts (in sequence assuming they don't work) Car has done only 18,000 miles and has never run better. They cancelled warning lights and they came up again straight away. Any ideas???

what service did they perform prior to these codes coming up?

it was a "full" service (whatever that means)done by a National Auto chain not by a VW dealer. I spoke to them about it last week and all they said was they don't touch anything that would cause this. I know they had a major problem changing the plugs because of their location

I'd take it back to them, sounds like a pinched wire maybe or something disturbed from the work done