No MAF? No problem!
Maybe this Baro sensor can be integrated somehow?
http://www.sparkfun.com/commerce/pro...oducts_id=8161
http://www.sparkfun.com/commerce/pro...oducts_id=8161
Maybe this Baro sensor can be integrated somehow?
http://www.sparkfun.com/commerce/pro...oducts_id=8161
http://www.sparkfun.com/commerce/pro...oducts_id=8161
ok, the way I understand it we need the barometric sensor at ignition on so the ecm knows the approx altitude where the car is at. Is it used by the ecm atall once started? if not why not leave the sensor conected to its conector , not conected to the intake ducting but tucked out of the way
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ok, the way I understand it we need the barometric sensor at ignition on so the ecm knows the approx altitude where the car is at. Is it used by the ecm atall once started? if not why not leave the sensor conected to its conector , not conected to the intake ducting but tucked out of the way
Because it is part of the entire MAF electronics and is big and bulky. I tried taking mine apart and making it smaller so that I could tuck it out of the way. Thats when it caught fire. I'm going to try a different approach after I get another MAF.
Also, the ECU will still make corrections off the baro after start up. With the MAFT Pro, I could output any voltage I wanted for baro input at any time. Large changes would have a drastic effect on AFR while the engine was running.
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When using something like a MAF translator that allow using DSMLink's Ignore IAT/Baro feature, the ECU's baro sensor input can be used for some aftermarket sensor such as a MAP sensor or a wideband O2 sensor. However, the baro input of the 2G ECU may not be compatible with the aftermarket sensor. The 2G ECU has a 3.3K ohm pull-down resistor (R39). This may put more load on the sensor than it can tolerate and still put out a proper signal. For example, a GM 3-bar sensor can only drive this input to 1.76 volts at maximum pressure. The new Delphi sensor seems to have a bit lower output impedance and will drive the 2G baro input to a little higher voltage at maximum sensor pressure, but it's still unsuitable.
Short of removing R39 from the ECU (described below), the 2G baro input is suitable for use only with very low impedance sensors (even a 50-ohm output impedance will produce a little over 1% of voltage offset). Since most sensor designs have a resistor in series with its output for protection, the 2G ECU's baro sensor input is probably not suitable for use with most sensors.
Short of removing R39 from the ECU (described below), the 2G baro input is suitable for use only with very low impedance sensors (even a 50-ohm output impedance will produce a little over 1% of voltage offset). Since most sensor designs have a resistor in series with its output for protection, the 2G ECU's baro sensor input is probably not suitable for use with most sensors.
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FORGET ABOUT BARO SENSOR!!
There is no reason to use it with the map path even if you have it save...Put a resistor.
BAro sensor is used to compensate lower pressures in MAS when you pump much air though the restrictive air filter. Mas measures air speed and multiplies on air pressure in sensor to get the correct air veight. With the map you dont need it anymore..You already measure pressure in the manifold... Even if you have baro working i reccommend to replace it with resistor .
There is no reason to use it with the map path even if you have it save...Put a resistor.
BAro sensor is used to compensate lower pressures in MAS when you pump much air though the restrictive air filter. Mas measures air speed and multiplies on air pressure in sensor to get the correct air veight. With the map you dont need it anymore..You already measure pressure in the manifold... Even if you have baro working i reccommend to replace it with resistor .
I am very interested in this....any way we can get this patch with the knock flash mod that tephra implemented on the 94170014 ROM?
My MAF is giving me problems/not working at all....so this would be awesome so I don't have to worry about it anymore.
I can provide the ROM that I need modified, and I do have the JDM map sensor....
~Zach
My MAF is giving me problems/not working at all....so this would be awesome so I don't have to worry about it anymore.
I can provide the ROM that I need modified, and I do have the JDM map sensor....
~Zach
I am very interested in this....any way we can get this patch with the knock flash mod that tephra implemented on the 94170014 ROM?
My MAF is giving me problems/not working at all....so this would be awesome so I don't have to worry about it anymore.
I can provide the ROM that I need modified, and I do have the JDM map sensor....
~Zach
My MAF is giving me problems/not working at all....so this would be awesome so I don't have to worry about it anymore.
I can provide the ROM that I need modified, and I do have the JDM map sensor....
~Zach
~Zach
I assumed it was just to keep the ECU Happy, however I realized my blowthrough sensor doesn't need the BARO sensor because of how the sensor itself works, it already provides a mass air output. The baro sensor is used for a reference value to calculate density because the stock evo sensor is a VOLUMETRIC airflow sensor.
I dont think that speed density is the best way to go, but you are already providing all the inputs needed by the ECU to calculate air density from the MAP sensor, TPS sensor, AIT sensor, so the baro sensor ultimately isn't needed.
I did originally think that you needed something other than a resistor for the baro sensor input as I had assumed it might throw a code from a fixed value, but after looking at my setup, the baro value has always been locked and i've never thrown a code.
So as long as your drivability isn't affected, and the fueling isn't somehow offset by the baro sensor value that cannot be compensated for dynamically, then there's no reason to keep it.
I dont think that speed density is the best way to go, but you are already providing all the inputs needed by the ECU to calculate air density from the MAP sensor, TPS sensor, AIT sensor, so the baro sensor ultimately isn't needed.
I did originally think that you needed something other than a resistor for the baro sensor input as I had assumed it might throw a code from a fixed value, but after looking at my setup, the baro value has always been locked and i've never thrown a code.
So as long as your drivability isn't affected, and the fueling isn't somehow offset by the baro sensor value that cannot be compensated for dynamically, then there's no reason to keep it.
Last edited by MalibuJack; Sep 27, 2007 at 04:57 AM.
When I ran a GM MAS and the baro was simulated by ECU+ (constant 99kpa) I had horrible problems when racing at low areas like Carolina Motorsports Park, since I lived and tuned in Blacksburg, VA (The mountains). It definately needed a tuning session each time. Unless you want to worry about altitude, the baro functionality should remain whether it is actual or dynamically simulated.
