As title.

Under what circumstances does the ECU read atmospheric pressure?

If it is only at start up then what happens when you drive up the side of a mountain?

I need to know, the reason is boring, but I need to know

 

I beleive it works on occasion when you release the throttle.

Of course this is no good for using the same pressure sensor for a MAF-MAP conversion!

I think you may need an independant sensor, or use some electronic trickery to send a fixed atmos value to the MAP line when requested by the pressure exchange solenoid is fired

Paul

 

Maybe it will just overfuel and pop a bit more than usual when it does this then Can't be worse than a VTA? I'll find out.

Looking at combined TMAP (temperature and MAP sensors) but all I could find went up to 1 bar absolute.

 

think Stephen Done said something on this a while ago.

and, think Paul is right - in that it checks when throttle is closed. At what frequency - who knows !

but obviously it does use it for relative calculations in the ECU. Seem to remember Steve saying that it would affect boost as the ECU limits / setpoints are all relative to atmo. (which obviously make sense!)
but if you're not using ECU for boost control , im not sure what else it would effect !?!

Steve