Ok, I have a 2001 C240 that is turning on the check engine light for a "P0173" code. I have cleaned the MAF, replaced the air filters, and inspected the air filter-MAF seal... all appears to be well, but it is still giving the code. I assume that replace the MAF is the next step, but just the MAF cartridge or the entire MAF? Opinions on MB branded Bosch part or standard Bosch replacement MAF? I'm still curious as the car not to date thrown a "P0170" code, just citing bank2 (driver's side); The MAF appears to service the entire engine, so I'd expect to see both codes.

Are there other things to review? I assume that dirty 02 sensor, clogged fuel injector, browning out coil, or fouled plug(s) would throw their own code; but would these be items to review in turn? Do those that have done this before have a recommended order of precedence in which to check/replace these?