ECM pmCAN Module Instruction Manual page 61

Holes look clean? You didn't drop the sensor, did you? The annulus should be even around
the ground electrode (i.e. everything should be symmetric and centered).
Blow it out one more time. Yes, there is a lot of blowing out. You need to clean out flakes
of soot, pieces of paper towel, and to evaporate any solvent. We recommend using DRY air.
We attach one of those in-line air line desiccant dryer filters to the entrance of our spray
nozzle. You can get those from a good auto parts or paint shop.
Lastly, attach the sensor to the pmCAN cable and electronics and see if the sensor shows low
PM, PN, IST, and ILK numbers when the sensor is held in air. Note that VHV is at about
1000V.
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