I dont know why or how the MAF effects the pressures but it does. Are u using EFILIVE Mine say this"" Use to turn on/off individual fault processing that will cause full line pressure in the transmission.
And it has the MAF codes listed PO101 103 102. Why they did that i dont know. Mine is under tranny diagnostics>Transmission DTC Fault Max Pressure Enablers. Not sure about HPtuners. But im still uncertain about patterns, this is just max pressure changes when these codes ae tripped

 

i'll take a look for that. i wonder if when you go to a 2bar os if it disables that.

 

The MAF measures air flow -> airflow is a base value with ignition advance to calculate Tq -> Tq is used to look up shift time, shift pressure, and Tq reduction during shifts.

If the MAF is reading the wrong value, or the max Tq timing table has been changed (don`t do it) the Tq calculation is thrown off.

If the MAF is reading the wrong value the Tq calculation is wrong, then you can FUBAR the transmission.

 

2 bar custom os simply adds functionality, it doesn't disable anything.

 

I think the MAF influences the tranny pressures indirectly.. The tranny pressures are determined by delivered engine TQ... If your MAF table is not tunned properly then you will not be making as much power as you should... Then when you remove the MAF or go SD then depending on how your VE table is tuned you could actually be making more power, thus the increase in tranny pressure... So indirectly it could cause it to increase the pressures, but if your MAF and VE table are both tunned properly then removing it should do nothing!!

The more TQ you make the more the pressures increase and vice versa...

My MAF is sitting on my shelf in my garage when I removed it I noticed no difference is shifting times or pressures... Then again my VE table is tuned...

BTW your friend that removed his MAF, I HOPE he bought an external IAT sensor...

 

I believe this was only a problem on the F-bodies or early trucks, not the one he has...

 

this makes since. basically his maf is prolly dirty or shot and after its all said and done in the tune its effecting his shift. he didn't take it off he just put mine on. i was trouble shooting my boost wiggle on my maf. but i just ordered my 2bar sensor so when that gets here i'll pull the maf and put in athe new map. i installed my new iat this weekend. installed it right into the manifold. i'll take pics once i get it all done.

 

Here is another thread about same subject. Notice what DC_Justin says:

http://forum.efilive.com/showthread....t=pressure+maf

 

thanks. i need to go and see what all i need to turn off or disable to go to 2bar sd. i still want to be able to run open and close loop with fuel trims and what not.

 

Do you use HPtuners or EFI Live... Mine were disabled on my stock tune, like I said I think it was only a problem on the earlier models...