hi all
help req. fault code p0420 catalyst system efficiency below threshold bank 1
car drives as nothing wrong except the engine light comes on ,car still performs as should. once reset with code reader .fine for a while .thought it was down to the petrol tried petrol from different places .
fault seems to happen when motorway driving.
this is driving me nuts.
thanks
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From DATSC website codes......
Generic OBD Error Code Details for P0420
Catalyst System Efficiency Below Threshold
What does this mean?
OBD Code P0420refers to
The catalytic converter has an oxygen sensor in front and behind it. When the vehicle is warm and running in closed loop mode, the upstream oxygen sensor waveform reading should fluctuate. The downstream O2 sensor reading should be fairly steady. Typically the P0420 code triggers the Check Engine Light if the readings of the two sensors are similar. This is indicative of (among other things) a converter that is not working as efficiently as it should be (according to specs).
