Introduction of Oxygen and Hydrogen

AI Thread Summary
Introducing small amounts of hydrogen and oxygen into an internal combustion engine affects sensor readings based on the combustion products. An O2 sensor detects changes in oxygen levels, indicating whether the engine is running rich or lean, while a CO2 sensor remains unaffected by hydrogen addition. The engine's Powertrain Control Module (PCM) adjusts the air-fuel mixture based on these sensor readings, aiming for stoichiometric combustion. The specific impact on fuel mixture depends on the ratio of hydrogen and oxygen added; a lean mixture prompts the PCM to enrich with gasoline, while a rich mixture has the opposite effect. Ultimately, the engine's performance and efficiency can be optimized by understanding these dynamics.
John1397
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Does introducing small amount of hydrogen and oxygen with gasoline into an internal combustion engine make the sensor read lean and and just enter more gasoline?

John
 
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what kind of sensor is it? CO2? or O2? Do you measure the combustion products only? Adding hydrogen will will consume O2, but not change CO2 in the products,so an O2 sensor will detect that you are burning richer and a CO2 sensor will not. Adding oxygen will of course make it lean and CO2 and O2 sensors will both pick this up.
 
I'm not a chemist but I am an auto tech. My assumption would be that it would depend on the ratio you added those elements. If they were added in a stoichometric ratio then the PCM would make no further changes due to complete combustion (you would get more work out of the engine though). If you added a lean hydrogen/oxygen mixture then the PCM would try and enrichen with gasoline until stoich is achieved and just the opposite would happen if you added a rich ratio.

BTW, auto engines use an O2 sensor. Most PCM's (that's the engine computer) use the O2 sensor to fine tune the air-fuel ratio once the engine is warmed up and running in closed loop mode.
 
Sounds like if you put hydrogen or gasoline into a motor the o2 sensor will send back a signal depending if you add to much fuel or to little it would send back a to rich or to lean signal regardless of kind of fuel is added. If you run a motor on 14:1 ratio of either hydrogen, gasoline, or even propane the o2 sensor will send back the same reading if I understand correctly?
 
John1397 said:
Sounds like if you put hydrogen or gasoline into a motor the o2 sensor will send back a signal depending if you add to much fuel or to little it would send back a to rich or to lean signal regardless of kind of fuel is added. If you run a motor on 14:1 ratio of either hydrogen, gasoline, or even propane the o2 sensor will send back the same reading if I understand correctly?

Exactly. Fuel is fuel. It's the incomplete combustion that is indirectly measured by the presence of free O2 in the exhaust that makes the engine computer make adjustments.

Also, bear in mind the engine PCM doesn't always desire 14:1. If you're working on a project, bear in mind that leaner mixtures are sometimes commanded by the PCM. Ratio's upwards of 55:1 during coasting can be called for (and some turn off the fuel completely for coasting conditions)
 
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