Water pressure sensor on 2008 Yamaha 250's

[cpowers121]

My first water pressure sensor malfuncioned on the port engine at 80 hours. The dealer replaced the sensor, wiring and control module. Now, 4 years later, the starboard sensor malfunctioned. I had purchased a spare several years ago and replaced the sensor. The engine runs fine. I discussed this with the original dealer and they asked if there was any corrosion in the connecting plug. There does not appear to be any on the three pins but there is a slight "trace" amount of brown residue on the female end of the connector and on the inside plastic part of the male connector. Should I be concerned? I also checked all of the pins and connectors on the control module. They were clean. I checked the port water sensor that was replaced in 2009 and it appeared to have a silicone grease like substance in the opening of the water inlet of the sensor. The mechanic said this was not grease but salt water residue. Is this correct as it looked and felt like silicone grease?
Thanks, Chuck

[rodbolt17]

the original sensors are and were under a recall.
usually I put dielectric grease on the pins.
easiest way to tell is by the hex size.
the 17mm hex is the old part the 21mm? hex is the correct part.

[cpowers121]

The original sensors were all 21mm. The original sensor on the starboard engine that just caused the engine to run erractically was completed blocked and encrusted with salt in the sensor opening.I do not know if the blockage in the sensor can cause a malfunction or if the sensor went bad. In any case the engine runs fine with the new sensor but I don't know if there was any electrolysis in the wiring that may eventually cause damage to the control module or the engine. This seems to be a common problem when the sensors go bad.

[boats.net]

Was the old one leaking water is why you replaced it?

[cpowers121]

No, the engine defaulted to idle..

[rodbolt17]

the issue with the original sensors,the diaphram would leak and force water up the wiring and into the ECM pins.
creates a world of weired issues.
some will throw a code and others wont.
the good one you can find at key on engine off with the laptop.