As some of you already I've replaced my 01 S40's engine with a 00 S40 engine and turbowith only 18K and the car is running great except:
The check engine light is on and local Parts Store found 12 codes of all kinds but I know none are correct because the engine is so new, one code is tranny relatedand..
Once in a while tranny upshift lightgoes on and the car picks up slow, I restart the car and everythings ok,
Again once in a while the brakes will get hard as if there is no power brakes,

My mechanic says drive around a couple of hundred miles, that should syncronize the computer and sensors then I may have to go to Volvo to reset the computer?

What do you think? What is the cheapest way of clearing this issue totally. I am trying to sell the car and can't drive the car around with no plates. But don't want to sell it with check engine light on either.

 

The parts store wouldn't clear them?

 

Hi, Tech. Long time no see.. The guy said he is not supposed to but I have another Parts store where the manager is a cool guy and will do it. Do you think once he clears them some won't come back on? Do I still have to drive the car for a couple of hundred miles? Thanks.

 

Clear the codes and start fresh. If they come back then take a closer look.