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Finally got the default ini file to load your msq.
Boy is this different than Megasquirt!
Loading your log into TS it does display the Baro Pressure as 212kpa to 214kpa so I am lost.
I am further lost at 138038.906 in the log because it shows MAP as 143kpa but Boost PSI of -10??????
Even further confused, in your I/O summery I do not see a MAP pin but baroPin is A7.
Can you post your ini file?

In the log, if you take "MAP" and subtract "Baro Pressure" it equals "Boost PSI"
Ex. at 138038.906: 143kpa - 213kpa = -70kpa = -10.1526PSI
At 138042.938: 25kpa - 213kpa = -188kpa = -27.2671PSI
So the math is correct, but the Baro Pressure is wack.

Wow... That does seem wack. I will post up the msq after work. Been wanting to hop over to something more mainstream (Fueltech, Haltech, etc), but would rather not as they are very expensive. I am very thankful of your help, I really appreciate it. Hopefully with your help I can make some ground. This may explain why I can't seem to map the boost gauge in Tuner Studio, nothing seems to work so I rely on my boost/vac gauge to monitor.

Depending on what you want sensors and output wise, Megasquirt isn't terribly expensive and has a large support forum.

But updating the firmware for your speeduino probably will take care of it since you are using a mid 2023 version and I saw there were several newer ones.

Sounds like the MAP sensor calibration is off? Or is it just the way it reads in MLV?

When running the MAP readings look correct.
Why the Baro Pressure is off which causes the Boost PSI to be off I can't tell.
In the msq it does not appear to have a separate sensor, but I am not familiar with speeduino.
Need to see the ini file.
Red = MAP
White = RPM
Green = Baro Pressure
Yellow = Boost PSI

Vac line connects to manifold (drivers side) after the blower. It forks off, one goes to FPR, one goes to ECU, and one goes to boost/vac gauge. My fuel table shows 100kpa (I'm 240ft above sea level) with key on, 70ish, which is Im not mistaken, is 10psi of vacuum. Am I correct?

Here is a link to my msq. Click here

I just enabled baro pressure on my copy of MLV. Here is what I have...

I still think this is probably in your ini file.
I am away from my work computer for the weekend where I have the default ini file for your file version, but if you can post your ini file I can compare it next week.

Sounds like the MAP sensor calibration is off? With the ECU powered & engine off it should read 100kpa +/-small amount. Is the map sensor mounted on the ecu or external?

The baro signal looks like an unconnected pin on the ecu that is floating.

What does the MAP read with key on, not started?
I am a little confused by your post what that reading is.
If 70 then Bruce is right about the MAP calibration.

I found this online about baro:

"BAROMETRIC CORRECTION - 2ND MAP SENSOR 2nd MAP sensor - cut off the unused 3 pins (pins 4-6) and on top of the MAP sensor on the board connecting pin 3 (+5V) and pin 2 (ground)also connected a 330 nf capacitor between pin 1 and ground. Pin 1 is the output and is connected through a 470 ohm 1/4 watt resistor to the A7 analog input pad for the Arduino chip. Configure using the Tools tab in Tunerstudio and choose Calibrate Pressure Sensors. Enable Baro and tell it which type of sensor you're using and connected to analog input pin A7. "

Go to tools tab and choose Calibrate Pressure Sensors.
Is Baro enabled?
If you don't have a second sensor and it is enabled then Bruce is right and you need to disable it.
In Megasquirt it is in a different place and that is why I didn't find a setting for it in TS with your msq.
I can't look until Monday.

Alexander_Monday wrote: ↑Sat May 31, 2025 5:47 am
Go to tools tab and choose Calibrate Pressure Sensors.
Is Baro enabled?
If you don't have a second sensor and it is enabled then Bruce is right and you need to disable it.
In Megasquirt it is in a different place and that is why I didn't find a setting for it in TS with your msq.
I can't look until Monday.

That fixed the baro. I disabled the "use external" one in the settings (it was a duplicate), baro defaults to 100 vice 212. Made a baro and vac/boost gauge. They seem to be working... but now the engine wont run?!?! Turned use external back on, now it runs but baro (212kpa) and boost gauge pegged at -30psi. Ugh, this thing is going to be the death of me. The MAP sensor is attached to the inside of the ECU. I have the vac line connected to it. Documentation shows MAP sensor is an "on-board 2.5bar" installed in ECU.

Let me know where to find that ini file you are asking for. Is it the "mainControler.ini" in the tune's folder?

Engine will only run with settings pictured below...

Couldn’t see any useful photos on the JoeBlow site but I assume it has the dual sensors fitted internally. Bit odd to use a pair of 2.5bar sensors since the baro only needs to read 100kpa +/-10% & you don’t get as much precision if the 0-5v signal is spread over 250kpa. Guess it’s cheaper to buy only 1 type of sensor.

The readings do seem a bit odd though.

Baro is more useful if the tune uses TPS for load, since altitude changes will not be included in the core fuel table look up.

I have a feeling that it is set up for a second sensor and either it is bad or it is looking for it on A7 input.

However, to cheat you could set "Baro Sensor kPa At 0.0 Volts(kpa)" and "Baro Sensor kPa At 5.0 Volts(kpa)" both equal to 100.

A7 pin is the usual input for Baro, on speeduino boards like the UA4C.