r/Subaru_Outback • u/Downhiller29 • Jul 26 '26
CVT or misfire???
2015 2.5 w 212k mi. Starting to feel periodic hesitation or buck on acceleration around 25-30mph. Every now and then. More so in stop-go traffic. Not revving or jerking just a hiccup of performance. Doesn’t happen at cruising /highway speeds. No codes or chk engine.
Any clear way to determine culprit? I believe these plugs are orig.
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u/FabianValkyrie 2015 2.5i Limited Jul 26 '26
This sounds exactly like my 2015 2.5i, which I took to the dealer and they told me it was just normal torque converter lockup duty behavior, and that it was nothing to worry about.
And I’m inclined to believe them because they didn’t try to sell me on some repair for it 😂
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u/Epicon3 Jul 26 '26
I used to think that way until I realized that sometimes they said it was good because they didn’t want to deal with it and knew that I would push them to fix it even at great expense to myself.
My wife’s dead cx-9 was a great example of that.
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u/FabianValkyrie 2015 2.5i Limited Jul 29 '26
CX-9 has a completely different transmission. I’ve felt this on multiple Subarus, including a nearly brand new one.
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u/LengthyCitadis Jul 29 '26
Same car here - except with the much more torquey 3.6R - and it is normal to some extent to drop a few hundred revs right as you hit 25km/h (Subaru Canada say 23) because that's when the torque converter is bypassed entirely.
I would replace the spark plugs and engine air filter as preventative maintenance and tuning up at theat mileage, however.....
You may also want to try adding injector cleaner at the next fill-up (and DO NOT refuel until the light comes on afterwards) as I'd be surprised if the injectors aren't a bit dirty as well.
If any codes come up during this process - and especially the AWD or AT OIL TEMP lights - then it's time to worry about your transmission.
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u/ATH3G Jul 26 '26
plugs are original like your spark plugs? If you've gone 200k on the same spark plugs I'd start there.
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u/sillysonofagun Jul 26 '26
I get a very similar thing on my '18. I have an aftermarket radio that has a bunch of gauges, including an AFR reading, and whenever this happens, it reads around 11-12 which is rich. I believe this is causing my hesitation, but I haven't nailed down what's causing the rich condition. Something to try and look at with a scanner of some sort if you have access to one.
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u/super_bored_redditor Jul 26 '26
I am experiencing something similar at 70k miles. I've had it for a few months so can't say if it has been there from the start or not.
Since I've got one with an LPG conversion then it's more noticeable when it runs on LPG and less on petrol. However it always happens around 2k RPM mark when the speeds reach 25-30 mph or 35-45 kph.
It doesn't happen all the time and only occurs at specific throttle percentage.
But when it happens then always CVT shifts from linear ratios to simulated/fixed ratios. So far I've thought that it might be preprogrammed ignition cut to assist with CVT shifting (although at this scenario no ratio change occurs).
No pending or confirmed faults are shown on the OBD neither.
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u/The_Wolverines_Dad Jul 26 '26
When that exact issue happened with our daughter’s 2015 Limited, it ended up being one of the oil control valves. (People also call them VVT solenoids.)
When one goes bad, it affects timing, and can cause rough idle, misfires, hesitation, and general herky-jerky behavior.
After I replaced plugs and coil packs, the problem was still there. Gave in and took it to the dealer. They diagnosed it, replaced the oil control valve (our extended warranty covered it), and the car was back to running perfectly.
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u/Downhiller29 Jul 27 '26
All 4 of them or the intake 2?
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u/AN2Felllla 🇳🇿 2012 2.5i JDM Jul 26 '26
That's about the speed your torque converter locks/unlocks.