P219A Code

JAMADOR · Sep 12, 2025

Car has intermittently thrown a P219A: Aif-Fuel Ratio Imbalance

Any quick checks fixes common this one to look into?

No performance effect that I can tell. Only possible symptom is it's averaging around 27mpg, but I've been having fun with it too, so that likely contributes to the lower MPG.

JAMADOR · Sep 13, 2025

Seems to have resolved itself? Haven't scanned codes, but the CEL is off now after about 100 miles on a fresh tank of gas [Shell 87]
Last tank was Costco 87

Grsemky · Sep 13, 2025

Try using premium gas.... I personally only put 91 in it, I live in AZ and get that California 91... My MPG averages 30.1 combined

Sprinkle_Star · Sep 13, 2025

Try a water remover fuel additive since condensation is more prevalent in the mornings this time of year.

JAMADOR · Sep 13, 2025

Thanks, if it returns, I'll try a few tanks of 93

JAMADOR · Monday at 4:35 PM

So, a maybe symptom.
CEL returns on a full tank & seems to go away when it gets down to around 3/4 full.
Will verify over the next tank or two to see if that's consistent.

Sam4 · Tuesday at 5:48 AM

Is it a corn-related thing? Are you using high alcohol/low octane fuel? The 3/4's makes me think of the evap system and hose - I literally only put in 10 gallons anymore.

JAMADOR · Tuesday at 7:39 AM

Not sure on the ethanol part.
Last 2 tanks have been Shell 87 from the same station. Would have to look, but think the 2 before that were Costco 87.
If the next tank does the same CEL from full to 3/4, I'll try a tank or 2 of 93 and see if that has any different effect.

Zeille · Tuesday at 9:43 AM

Change o2 sensors? I had a p219a issue and replaced upstream & downstream and it went away. It was just an underlying code and never actually threw the light, but just a suggestion

JAMADOR · Tuesday at 9:47 AM

O2 sensor(s) or evap were my leading 2 guesses.
Evap more because it seems to be consistent with a full fuel fill.

rallytaff · Tuesday at 12:54 PM

Have never used anything except 91 in my 2014. No issues at all!

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P219A Code

JAMADOR

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