realtime baro settings making MS crap out

[beepee]

Twice this has happened.

1. Drive somewhere, cut off car.
2. Spend an hour or so wherever.
3. Get back in car, primes but no start.
4. TunerStudio complains of config error, which I can't recall exactly but it was something to do with the I/O pin assigned to the baro sensors.
5. Disable realtime baro, power cycle, start car
6. Re-enable realtime baro, burn, power cycle, everything is still good

After this, I can start and restart the car as much as I want, no problem. But it seems like if I let it sit with realtime baro enabled, something gets ****ed and the settings get corrupt.

Both baro sensors are working (tested on bench). It's the DIYautotune mapdaddy 4bar and I am confident it's installed properly. Used the same pin for realtime baro as in the DIY guide, and the sensor responds correctly.

so, wtf?

 

[Karl Buchka]

Is anything else configured to use that same input pin?

 

[beepee]

I am pretty sure that nothing is. Only modifications to my MS are:
TIP122 for PWM IAC (that is disabled currently)
2xBIP373 for future wasted spark (also currently disabled, using one of the LED output pins to directly drive a bosch ignitor)

The realtime baro is connected to JS5, just as it is in the DIYAutoTune guide.

Does anything else use JS5 by default? I assumed that it was 'free'; there are too many ****ing dialogs in tunerstudio to figure out what every I/O pin is utilized for in a sane matter.

 

[550]

What version of MS are you running? MS2?

 

[1983Turbo242]

Can you just run it without a baro sensor? Are you tuning it in alpha n or speed density?

 

[beepee]

What version of MS are you running? MS2?

Yeah, it's MS2/Extra... can't remember the version, but I checked a few weeks ago and it was one revision behind current. Latest patch notes don't say anything about baro input.

Can you just run it without a baro sensor? Are you tuning it in alpha n or speed density?

Only speed density.

I have the baro turned off currently and it works fine, but it's annoying... I bought it, and I want it to work dammit! And it DID work, and it does work. It's just like MS gets confused about the pin assignment, even though it shows correct in the configuration. But it won't start until I disable and re-enable baro correction. WTF.

 

[1983Turbo242]

Hopefully one of these ms gurus will he able to help find the problem, but for my own interest, what is the purpose of the baro sensor on a speed density tune?

 

[Karl Buchka]

Speed density is, as the name implies, dependent on actually knowing the density of the air.

 

[1983Turbo242]

Speed density is, as the name implies, dependent on actually knowing the density of the air.

Don't most speed density setups just rely on the IAT and map to calculate density?

 

[550]

When you are only using one sensor it will get the barometric pressure for that instance. So while driving it can obviously change, but it won't know what because it's still using the past value as the base.

 

[Karl Buchka]

Don't most speed density setups just rely on the IAT and map to calculate density?

Here's a good run down on how speed density calculations are performed:

http://www.megamanual.com/v22manual/mfuel.htm