Carbon Build up on 04 745i
I have code 2761 Secondary air bank one, couldn't pass inspection, Dealer replaced 2 valves and hoses going to valves. They state its carbon build up in the heads. Spoke to service manager today and he feels there is a blockage in the tube going into the engine on the left side since the air pressure is to low. I'm thinking of Seafoaming the car to see if I can loosen up some of the deposits. He also stated that the rear o2 sensor is throwing a code but didn't replace it yet. Do you think we should try and replace the sensor or is this just a waste of money?