If you have moved the car without giving it a chance to warm up (ie back it out of a driveway only) and then do the same thing again to move it back in, the sensor is actually detecting that the emissions are incorrect.

This is because there is excessive fuel (from start ups) that hasn't had time to be blown out as the car has only had a short run.

It happened to me.... Take it for a spin on a reasonable journey and next time you start her up it should be fine.

If not, then look for a further problem.

Cheers

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