"cat Efficiency Below Threshold" Wtf?

[vikvallabh82]

While driving along an A road my engine management light came on. Thankfully I could dive into a reputable local mechanic who read the error code and it came back with ""CAT efficiency below threshold"... now I am aware of a number of possible casues, the mechanic cleared the code, and I continued the rest of my journey (27 miles of motorway and dual carriageway) with no further incident.

Anyone had this before? Any ideas?

Vik

[215 compressor]

It means the cat isn,t wotking effiecntly enough so you may well need a new cat

[mr-p]

it may not be the cat at all before you jump in at the deep end. The o2 sensor may be dirty and clogged up and sending an incorrect signal id take them out and give them a clean first

[vikvallabh82]

Is there a guide for the o2 wsensor removal onthe forum?

[oldcodger]

Is there a guide for the o2 wsensor removal onthe forum?

Hey,

Check out sites like this before you do anything to your oxygen sensors, you will probably bugger them up totally if you try cleaning them manually.

Oxyen Sensor cleaning

Better still, wait until its a regular probelm of the check light coming on, a single occurrance is not enough to warrant loads of work.

A MOT type emmissions test will tell you if anything is really wrong and cost a lot less.