2.3L ('83-'97) Manifold Absolute or Barometric Pressure sensors?

[Chapap]

Wondering if this engine has either a MAP or BPS. I’m guessing no MAP cause, as I understand, it has the same function as the MAF. I don’t know about the Barometric Absolute Pressure Sensor though. I just ran across it while perusing Rock Auto.

 

[Dirtman]

There was never a barometric pressure sensor on any ranger (maybe the 2019+ ones). Barometric pressure is outside air pressure, MAP sensor is pressure inside the intake. Depending on the year it can have both a MAP sensor and a MAF sensor however. MAF and MAP do similar things in a different way and modern engines use both for more precise data. The PCM can determine the barometric pressure by reading the MAP sensor before the engine starts as that reading will be normal outside air pressure until the engine is running. Some cars do use a separate baro sensor but the ranger never did.

 

[Chapap]

Well that must be some very fine tuning being done if they take into account barometric press. Somewhat related: Is the intake air temp sensor a critical sensor?

 

[Dirtman]

Well that must be some very fine tuning being done if they take into account barometric press. Somewhat related: Is the intake air temp sensor a critical sensor?

Air fuel ratios are based on oxygen. If the computer cannot tell how much oxygen is in a given volume of air the air fuel ratio will be off. Higher barometric pressure means more oxygen in a given volume of air. Less oxygen the higher in the atmosphere you go because air is thinner. Air temperature directly effects the fuel air ratio too because hotter air also has less oxygen than colder air. So the MAF, MAP, IAT, and BARO readings all combine that data to make the perfect air fuel ratio. So yes the intake air temp sensor is important.

 

[Chapap]

Air fuel ratios are based on oxygen. If the computer cannot tell how much oxygen is in a given volume of air the air fuel ratio will be off. Higher barometric pressure means more oxygen in a given volume of air. Less oxygen the higher in the atmosphere you go because air is thinner. Air temperature directly effects the fuel air ratio too because hotter air also has less oxygen than colder air. So the MAF, MAP, IAT, and BARO readings all combine that data to make the perfect air fuel ratio. So yes the intake air temp sensor is important.

i would have thought that was more or less theoretical. I never adjust anything on a carbureted engine aside from cleaning the carb every once and again.

 

[Dirtman]

i would have thought that was more or less theoretical. I never adjust anything on a carbureted engine aside from cleaning the carb every once and again.

And that's why fuel injection is oooodles more efficient than a carb. Just because a carbed engine can "run" without adjustment doesn't mean its running at peak efficiency. Take a carbed engine and slap even a basic throttle body fuel injection system on it like a holley sniper setup and not only will you gain power, you'll gain fuel efficiency, and it'll run cleaner all in one shot. Electronic fuel injection is always making adjustments based on a ton of sensor data, carbs just kinda squirt fuel and hope it's close enough to the right mix to work...

 

[scotts90ranger]

MAP and MAF are just two different ways of doing things... Using a MAP sensor is referred to as "Speed Density" since it is using the density of the air and the speed of the engine to adjust the fuel for different conditions. This is arguably the most robust way of doing things but MAF is more accurate so for modern emissions regulations almost everything went to MAF... Combine either with closed loop fueling (using oxygen sensors) and you can get pretty good unless a crazy cam is involved...

I don't think any Ranger engine used MAF and BARO at the same time, but the turbo 2.3L uses a baro sensor and the vane airflow sensor which works like a MAF...

 

[Dirtman]

Modern vehicles essentially have an entire weather station built into them. Even my lowly 2009 ranger reads barometric pressure and the outside ambient air temperature. I wouldn't be surprised if even newer vehicles had hygrometers since humidity also factors into the air fuel ratio...