I had a couple of codes throw today on my E53! I am a new owner of a 181K '02 E53. Plz help.
08 Signal, MAFS* REPLACED
E4 Fuel Trim Bank 2, permissible range exceeded
E3 Fuel Trim Bank 1, permissible range exceeded
A8 Thermostat, map cooling, mechanical, jammed open
I did some reasearch on the boards to find that I might need to change my thermostat (gonna change my water pump, too). Shoud I replace my valve cover gasket and CCV hoses to make sure they aren't leaking? How do I do a vaccum leak test? Also is it time to replace the DISA valve?