Oxygen sensors

[Gerry Patterson]

Codes don't tell you what part is bad. Codes tell you what page to open up the book to and do the necessary pinpoint test. Proper diagnosis is 85% of the job, anybody can throw parts at it costing you lots of money unnecessary. A good DVOM and the ability to read live data are key.

Thank you for that. Diagnosis is what I’m working on with the questions I’m asking.
Why would there be water in the exhaust?
Would something like a bad injector cause the emission control system to go out of spec, tricking the computer to thinking there’s a bad sensor?
Why would the computer throw a code when running the engine with the post car sensor unplugged, but not true a code with the pre cat sensor unplugged?

 

[Brite Idea]

water in the exhaust is how it exits the boat. My mechanic hates O2 sensors because they're so troublesome. He also told me that in a saltwater environment the salt crystalizes and causes alarms. There's a kit to bypass the down stream O2 sensors but I like the fitting that moves them further away from the water. I'm going to install them before I splash.