P219A Code

[JAMADOR]

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]

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]

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]

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

 

[JAMADOR]

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

 

[JAMADOR]

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]

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]

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]

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]

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

 

[rallytaff]

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

 

[JAMADOR]

Seems this code is persisting now. CEL came back on at about 3/4 of the last tank. Filled up this morning at 1/8 & still have the light on.
Think I may throw a new set of O2 sensors at it, seeing Bosch, Denso & Motorcraft, with the MC being the priciest of the 3, but being the 'Ford' branded would be my first thought to use. Any reason to not go with the Bosch or Denso?

Also, if that doesn't resolve anything. Where is the Vapor Canister located? The parts diagram doesn't really give a lot of location indication.

Or, are there any parts to inspect prior to throwing some $ at it? I had a persistent lean condition on my Mini that the FiST replaced. Turned out to be a tear in the intake boot, between the MAF & TB. Was able to patch it with some high-temp liquid gasket & it held fine up until trading it in.

 

[Zeille]

Seems this code is persisting now. CEL came back on at about 3/4 of the last tank. Filled up this morning at 1/8 & still have the light on.
Think I may throw a new set of O2 sensors at it, seeing Bosch, Denso & Motorcraft, with the MC being the priciest of the 3, but being the 'Ford' branded would be my first thought to use. Any reason to not go with the Bosch or Denso?

i'd just opt for Denso, it worked out on my car with the p219a that I had, i replaced upstream & downstream and it went away, never came back. i think denso was cheaper too

 

[JAMADOR]

The Denso sensors are about 1/3 [DS] & 2/3 [US] the price of the MC options, at RockAuto

 

[Zeille]

The Denso sensors are about 1/3 [DS] & 2/3 [US] the price of the MC options, at RockAuto

that's a no brainer, just get those

 

[JAMADOR]

Thanks.
Just crossed 100k, probably do spark plugs too.

 

[JAMADOR]

New plugs & both O2 sensors [Denso] ordered. Hopefully that does it. Needed plugs anyway. 4 plugs & both sensors from RockAuto was less than just the sensors [Motorcraft] from a few Ford parts warehouses.