hi everyone,

My mechanic who lives around 160 miles from me changed my air flow sensor. When i picked the car up, the car's idle was surging badly. He could not figure it out.
Anyway i drove home and booked it in with the main dealer. They ran a diagnostic and told me that the C/O was on 9.2% when it should be around 1% and that the hydrocarbons were at around 2500, when they should be at around 300.
My question is, has any damage been done driving that 160 miles, plus the 10 miles to the dealer?
The dealer told me that now they have adjusted everything, its running sweet...
Just need some reassurance from you guys!
Many thanks!