E200 Kompressor ( W210) P0420 codes

[brens-e200]

hi all

i had been getting a P0420 code once a month and now today I got 2 in a row. The car runs fine with this code but i would rather fix it.

This is the log i pulled from my OBD reader and was wondering where do i start in diagnosing the problem.

meta-info header:Error Codes
file version:1
type:5
time:1420566218089
name:Trouble Codes
codes0420,
codes_p:
codes_raw:43042000000000;;
codes_p_raw:47000000000000;;
*****
Error Codes
P0420
Catalyst System Efficiency Below Threshold
Calculated engine load value (EngineLoad) 32.94 %
Vehicle speed (Speed) 63 MPH
Engine RPM (RPM) 2483 rpm
Long term fuel % trim Bank 1 (LTFT1) -7.03 %
Short term fuel % trim Bank 1 (STFT1) -0.78 %
Engine coolant temperature (ECT) 176 °F
Fuel system status (FSS) Closedloop:usingO2sensorforfuelmix


Thanks in advance

brendan

 

[alexanderfoti]

Ideally get it on star and have a look at the actual values from the O2 sensors pre and post cat. A good OBD reader will show you the values from them too.

You either have a broken cat, or a faulty O2 sensor (which I would say is more likely).

 

[brens-e200]

thanks

hi

thanks for the help , does the code point towards either the pre or post cat O2 sensors would you reckon ?.

I'am using the Android OBD car doctor so i will give that a shot regarding O2 sensor readings.

thanks again and here's hoping its not the cat

brendan

Ideally get it on star and have a look at the actual values from the O2 sensors pre and post cat. A good OBD reader will show you the values from them too.

You either have a broken cat, or a faulty O2 sensor (which I would say is more likely).

 

[alexanderfoti]

It will be refering to the Post O2 sensors, BUT, if the pre sensor is faulty it would also give this reading.