non-EGR auto trans

[idosubaru]

it looks like a non-EGR engine causes some minor shifting issues in automatic transmissions. i'm going to entertain the idea of fixing it or learn something along the way if i don't.

 

installing EGR isn't an option, i'll continue to shift manually.

does anyone have any idea of why this happens or a solution?

 

i think nipper said it was likely related to MAP readings which are tied into the EGR system?

 

is there any way to find 96+ non-EGR transmission vehicle?

would the TCU's differ at all?

 

i had a 97 automatic Impreza OBS EJ22 that did not have EGR and it looked completely factory. as a matter of fact the engine is in my garage and the intake is in my Legacy. no EGR stuff at all, no plugged holes either. but i've never seen another, so doubt i can find one. and it's hard to believe they'd have a different TCU anyway. wish i still had that car.

[screwbaru2]

The 97 legos MT were non-egr. Found that out the hard way. But they are MT not AT.

The shifting must have something to do with less engine vac on accel. egr closes the TCU reads that as a signal to downshift. Probably way over simplyfied but something along those lines.

[idosubaru]

The shifting must have something to do with less engine vac on accel. egr closes the TCU reads that as a signal to downshift. Probably way over simplyfied but something along those lines.

 

nipper put it this way in another thread:

The map sensor in soobies is a dual sensor. There is a flip valve. The valve flips so it can read atmospheric and engine vacume. If this valve isnt flipping,you wont get a atmosphere or manifold reading and that would cause no shift.

 

egr may boost or lower the vac enough to force a downshift normally.

 

nipper

 

thanks guys.