# Stumbling at part throttle at speed



## 17Hatch6MT (Dec 28, 2015)

Drove it again today. Ran great, no stumbling. Did a few miles at 80 mph on the expressway. About 35 miles total. Last 25 miles DIC mpg was about 47, translates to about 44-45 actual. No complaints today.


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## 17Hatch6MT (Dec 28, 2015)

Seems to be a frequent occurrence now. Going to moderate throttle on at mid rpms (say, 2000-2500), stumbles and rattles a bit and then catches but with less power than expected for the throttle position and rpm. Most noticeable when hot, or at least, I noticed it more recently and the weather has been warm.


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## WillL84 (Aug 5, 2019)

Does the check engine light flash when it happens?


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## 17Hatch6MT (Dec 28, 2015)

No check engine light. Not that I noticed. I'll watch closer next time. Is not lit normally.


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## WillL84 (Aug 5, 2019)

If it flashes when the stumbling occurs that's some kind of misfire or knock. Do you run 91 or 93 octane? How many miles?


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## 17Hatch6MT (Dec 28, 2015)

Thanks... I always put in 93. 19,000 miles. I don't think the CEL is coming on at all; but again, I wasn't watching. Always thought it would stay lit if it came on at all.


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## WillL84 (Aug 5, 2019)

I believe if it's knock or a misfire it won't stay on, it'll just flash it blink as it happens. I'm at 15k on my 17 and I'm trying to prevent the dreaded cracked piston problem as much as possible lol


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