P0172 Mercedes-Benz -

Question

I have 3 fault codes P0101 P0102 and P0172 maf sensor cleaned and slight improvement so do i change maf or oxygen.sensor

Answer 1

P0172 Fuel trim too rich bank Bank 1

P0101 MAF circuit range/ perfromance

P0102 MAF circuit low input

If you clean the MAF and there is a improvement the problem is with the MAF. The 02 sensor is just reporting the fuel trim that the MAF went out of fuel trim  limit.

 When it comes to a MAF for a MBZ. A out of range MAF will set fuel trim codes such as P0170 , P0171, P0172, P0173, with no drivability, and under a scan tool data stream it will be in specifications , but it will set fuel trim codes . and go out of fuel trim limits.