my 93 wrx goes in the garage tomorrow to have a cat back powerflow fitted.
I'm looking at fitting a stainless down pipe later this year, but when the bloke checked he said that the sensor was at the bottom of the down pipe and he had only seen them with the sensor higher up and it seemed smaller than usuall any one got any ideas as the pipe already has a hole higher up. Also what does this sensor do?

 

sounds like the Cat on fire sensor.
Basically an overheat sensor that will light a bulb on the dash to tell you to slow down.
It can be removed without harm to the running of the engine, as it's only a temp sensor.
I've heard on here that some cars seem to flash the CEL if this sensor is disconnected, but the ones I've done (i.e removed completely) have not. so it may need to be left connected and secured to the loom away from the exhaust.

looking at the tip of the sensor will tell you whether it's a temp sensor or a lambda sensor straight away, the temp sensor will just be a probe and the lambda will have holes in it to enable it to "sniff" the exhaust gas.


Andy

 

cheers mate, very helpfulnow't to worry about