Hi all: the pyrometer sensor is tapped in the exhaust manifold and has worked great for years. Lately it's been erratic and gives readings that seem to be about 250 degrees off. Does the sensor need to be cleaned, scrubbed or somehow maintained ever so often?

 

IIRC, they can accumulate carbon chunks which would impact on accuracy and sometimes the darn things just burn up at the tip and become totally unreliable. Just take it out of the exh man, assuming that's where you have plumbed it and visually examine it. BTW, every picture tells a story if you are unsure of what your visual exam is telling you.

Cheers!

Mike

 

I've found that the connections are critical. Often when mine goes goofy, it'll just be the screw and terminal splices to the thermocouple under the hood. Other times, cleaning the connections on the back of the meter fixes it.
The voltages and currents involves are extremely small.