Hey everyone, after the last time this happened a few months ago and topping the car up with ATF the car has run pretty much like a dream, but would still shudder/stall out if I reversed slowly up a hill (for example reversing out of Jackie's parking lot haha). Car drives completely fine otherwise, acceleration feels fine, etc. Today the issue happened again when I was "coasting" without giving it gas into a car wash stall, and the car stalled out. Symptoms seem similar to these two threads, but I don't have any sputtering or stalling at high speeds, this is basically exclusively a problem when I'm in a parking lot coasting around or I coast up to a red light.
http://www.westernsubaruclub.com/smf/index.php?topic=53400.0 http://www.westernsubaruclub.com/smf/index.php?topic=53479.0Things I have done is look at the A/F ratio on the AP, clean the MAF sensor, check transmission fluid level and appearance (looks decent to me), and check the air filter. Things I have not done yet is just go to Jackie for a ATF change/flush, and maybe see if there are any metal shavings or something in there that might indicate the transmission is screwed? Spark plugs were changed recently, throttle body was cleaned, etc. and I don't think I have a vacuum leak.
The major problem is that I can't seem to be able to reproduce this problem consistently. I've taken it to Jackie and tried to reproduce it to no avail, and last time I was at Subaru for the airbag recall I told them about it and they checked it out and couldn't find any problems either and couldn't recreate the problem. It's super rare that it happens, but I guess it's "consistently" rare, like I can count on this problem happening at least once out of a few times I drive, but I can't predict when it happens, because sometimes it happens when I'm going up a hill, sometimes just on flat ground, sometimes it doesn't happen at all.
Googling as well as searching on LGT, and looking at suggestions made by other members on here, it seems like the various possibilities include front o2 sensor needs changing, torque converter may be bad, fuel pump is bad, oil control valve problem, vacuum leak, or transmission is about to blow up and I'll be out a few grand.
There isn't a check engine light, and just like a few months ago there are no codes when I scan it. It's super intermittent and if I brake/give it gas the problem starts so I know how to "get rid of it", I just don't want this to be the start of a big problem that costs me a lot in the future/just want to fix it before it gets bad.
Thank you so much for your help!