To be fair I wouldn't know what's inside the MOT station testing box.
It could be a standard WB sensor for all I know or they could use a different detection method.
But If I recall the other day getting my MOT it fannied about for a bit (warming up??) then did a free air sample, before being stuck in the exhaust pipe.
Similar to my LM-1 doing a free air at inital startup for getting a reference.
Since WBO2's have a heater built in to get the sensor up to working temp the distance doesn't matter in so far as the exhaust loosing temperature as it's the element that will regulate it at the operational temperature. So distance from the exhaust ports in terms of temperature of the gas isn't really a problem.
It could be a standard WB sensor for all I know or they could use a different detection method.
But If I recall the other day getting my MOT it fannied about for a bit (warming up??) then did a free air sample, before being stuck in the exhaust pipe.
Similar to my LM-1 doing a free air at inital startup for getting a reference.
Since WBO2's have a heater built in to get the sensor up to working temp the distance doesn't matter in so far as the exhaust loosing temperature as it's the element that will regulate it at the operational temperature. So distance from the exhaust ports in terms of temperature of the gas isn't really a problem.