Well I had the engine supported while running it without the tranny to keep the fan out of the shroud, and I felt like it still had a slow revving issue, though I'm not familiar enough with these engines to say for sure. That's why I put up the video. I'm flooring it when I show the tach in the video.I wonder if you have a kinked tube somewhere. It ran fine with the engine hanging....
It may be internally frequency based but as far as the pcm is concerned it's a 5v ref and ground and signal. I just put resistors between 5v ref and signal to pcm until I got 14.7 psi. Idk how the sensor itself functions, but it's converted to a 0v-5v pcm input like everything else.I thought the Baro sensor was frequency based similar to the MAP sensor in the 97s.
|Barometric Pressure (BARO) Sensor|
Well it works like every other 5v ref sensor I've ever encountered. Input to pcm is a steady voltage between 0 and 5. I set it for my altitude with resistors and its working just fine. 🤷♂️Just for information, from the PCED:
Barometric Pressure (BARO) Sensor
The barometric pressure (BARO) sensor is a variable capacitance sensor that, when supplied with a 5-volt reference signal from the powertrain control module (PCM), produces a linear analog voltage signal that indicates pressure.
Timing Control — The BARO signal is used to determine altitude to adjust timing and fuel quantity to optimize engine operation and control smoke throughout all altitude conditions.
Glow Plug Control — The BARO signal is one of the variables used to calculate glow plug ON time. At higher altitudes glow plug on time is increased to insure faster clean up of start-up smoke.
A BARO signal that is detected out of range high or low by the PCM will cause the PCM to ignore the BARO signal and use the manifold absolute pressure (MAP) signal generated at low idle as an indication of barometric pressure.
The OBS MAP does output a variable frequency signal vice a voltage. Cheers!