P0521 Mercedes-Benz -

Question

1. List item Merc 2007 c350 :

Fault codes as follows p172, p 175 and from time to time 0521 with out p in the front on the launch machine..
We have already changed oxygen sensors and these faults come back on after every 300 kms or so..

Would really appreciate your assistance ..

Regards
Kimeshan

Answer 1

Hi there,

The codes P0172 and P0175 indicate the fuel mix is too rich on bank 1 and 2. Here is a list of possible causes.

P0172 MERCEDES-BENZ - System Too Rich Bank 1

Read more: https://www.autocodes.com/p0172_mercedes-benz.html

P0521 indicates an issue with the oil pressure sensor. Here is a list of possible causes.

P0521 MERCEDES-BENZ - Engine Oil Pressure Sensor/Switch Circuit Range/Performance

Read more: https://www.autocodes.com/p0521_mercedes-benz.html