- Sat Dec 21, 2024 7:48 pm
#70303
I can't answer specifically, as I do not know your project goals, nor how you are applying O2 data to it specifically. +1 @jonbill, as the O2 sensor is a spot-check of relative values. Look at it this way - there is no reason for different cylinders on the same engine to be running substantially differently, unless something is wrong. This makes additional O2 bank sensors failure indicators for common applications, not usually tuning or operating sensors.
Other issues exist, such as which sensor has authority? If one reads differently, do we lean for the rich reading? Enrich for the lean one? Is the anomaly a misfire? A failing sensor? Are we helping or making it worse? This is why most systems watch one sensor. If it's working correctly, it is reasonably representative of all cylinders.
But they use per-cylinder O2 in high-$ racing! Yes, and each cylinder runs fine for common uses, but they are looking to squeeze every drop of control and efficiency out of each individual cylinder. The last percent. Different goals. But the use is the same as a failure indicator, of one cylinder failing to operate at the precise Lambda previously determined to be optimal for that condition, relative to others. This is an important perspective, as knowing one should know them all, yes?
Much as every intake port is slightly different in the engine, so is every injector, every exhaust port, each cylinder head temperature, every intake runner, every exhaust header path, etc. This is where special applications can use per-cylinder tuning (some control enabled by sequential) for hair-splitting efficiency. That is not 99% of users, but extremely valuable to those that can really make use of it to reach their goals.
Think of why you want more than one O2 (or other per-cylinder/bank relative readings, such as EGT), and what that could or would accomplish. Does it really get you anything you can use? Exactly what does that info get you? Is the info valid, or simple production variation in values? How do you know? And how would you use the info if it is valid? Does that chain result in reaching a goal? Ah, back to the first question in any project - what are the goals?
In-conclusion, spark plug reading is a skill but simply comparing spark plugs for anomalies is appropriate for most applications, in order to ensure there is nothing markedly wrong. Failure indicators. If your needs are more specific, or if you have the ability to use O2 data for diagnostics, that's a different scenario. Your project, your goals, and your call. Hope that helps.
-= If it was easy, everyone would do it =-