Hi Scotty 

2017 Subaru Forester xt cvt 2.0 turbo

i had a problem with my Subaru it was almost stalling when I slow down at a light and a little rough idle then eventually it got a P015a and b 

first thing I did was

replace plugs, air filter, change pcv valve and cleaned throttle body, ran a bit better doesnt almost stall but there is still hesitation. Eventually I change the sensor 1 and sprayed the maf sensor and it made the idling better the fuel economy was great  but the hesitation was still there. There would be days where it’ll run perfect  then when you drive longer and the engine is hotter it will start the hesitation. I kept putting royal purple fuel line cleaner every now and again. Didn’t do a thing.  eventually it started cold start rough idling to I think misfiring when idling but not getting any codes and running rough to sluggish and I just know it’s not right. I got a injector cleaning service from the dealer but it did not do anything. Took it to so many Subaru specialists now but they can’t find anything or can’t replicate the hesitation I’m telling them and showing in video of the tachometer dipping and dipping when I accelerate. Now it doesn’t run right all the time now Thanks

no difference if I use Costco premium to shell v power

Thank you 

j from Alberta Canada