Q: Sensor messed up

asked by on February 08, 2016

The catalyst monitor is not ready. It has been like this for the last 3,000 miles, and I am not sure why. Maybe a sensor is messed up.

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Hello. There should be a Check Engine warning light on the dash display. It could also be a loose connection if you recently had exhaust work done. If you have any failure in the catalyst sensors or wiring, it should make the engine warning light go on. These sensors and the engine management are very sensitive to changes which will cause the warning light to come on. If you do not have a scanner for your BMW, then go to a qualified technician or shop that does BMWs to have the problem diagnosed.

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