Thanks. Maybe I didn't ask enough. The engine has Wrecking yard yellow markings in a couple of places, so I'm thinking that maybe the engine has been replaced? the car has been in a front end collision, not sure how bad. Has a new hood, radiator support etc. So is there a code on the engine itself? ...

I was told that it could be that the "Cabin air filter" could be dirty.

I need to find which engine I have in my 1999 Volvo V-70 by using the vin Number