P219A and P219B on a 2018-2019 Honda Odyssey: Start With the Fuel Injectors

P219A and P219B on a 2018-2019 Honda Odyssey (3.5L J35Y7) mean one cylinder is burning a different air-fuel mix than its neighbors on the rear bank (P219A) or the front bank (P219B). Worn or clogged fuel injectors are the most likely cause. The fastest confirm is to swap the problem cylinder's injector with another and rerun the cylinder air-fuel test. A guide cannot set a safe driving limit for your van, so get it diagnosed.

What does P219A and P219B mean on a 2018-2019 Odyssey?

P219A (Air-Fuel Ratio Variation of Cylinder, Bank 1, Rear Bank) and P219B (Bank 2, Front Bank) are the same check on opposite banks. Bank 1 is the rear bank (cylinders 1 to 3) and bank 2 is the front bank (cylinders 4 to 6). The PCM watches the rear A/F sensor (bank 1, sensor 1) for P219A and the front A/F sensor (bank 2, sensor 1) for P219B.

Every cylinder on a bank feeds that one sensor in turn, so a cylinder running richer or leaner makes the signal swing in step with the firing cycle (two engine revolutions). The PCM also varies the air-fuel ratio on purpose, separates the two swings, and stores the code when the cylinder swing is large enough against its own variation.

The PCM sets the code when the integrated A/F sensor output variation value is 5 or more within 11.5 seconds. All of these must hold:

• The monitor runs once per driving cycle and takes 7.5 to 11.5 seconds.
• Engine coolant temperature (ECT sensor 1) is 156 degrees F (69 degrees C) or higher.
• Engine speed is 3,200 rpm or lower.
• Intake air amount at 1,500 rpm is between 0.25 g (0.009 oz) and 0.58 g (0.02 oz).
• Intake air amount at 2,400 rpm is between 0.25 g (0.009 oz) and 0.6 g (0.021 oz).

The first detection stores a pending code. If the fault returns on the next drive cycle, the MIL comes on and the PCM stores the confirmed code, freeze data and an on-board snapshot.

That makes it a two drive cycle code. The MIL goes out if the fault does not return in three consecutive drive cycles with similar engine conditions. A scan tool or disconnecting the 12 volt battery also clears the codes, freeze data and snapshot.

Two sibling codes watch the same rear sensor. P0130 (out of range) runs continuously and sets at 4.66 V or more for 7.0 seconds or longer. P0133 (slow response) runs once per driving cycle, with a limit that depends on engine speed and load.

What symptoms does P219A and P219B cause on the Odyssey?

• Check engine light on
• Misfire codes stored with it
• A catalyst efficiency code (P0420 or P0430) stored with it

What causes P219A and P219B on the Odyssey, most likely first?

How do you diagnose P219A and P219B on a 2018-2019 Odyssey?

You will need a scan tool, a compression gauge, feeler gauges, a torque wrench, throttle plate cleaner and basic hand tools.

On a 2018-2019 van that qualifies by VIN, Honda's own path skips the testing and goes straight to new fuel injectors, with at least 5,000 miles on the odometer. A dealer confirms eligibility by VIN. Any van that does not qualify gets the steps above.

That job means relieving fuel pressure, disconnecting the 12 volt battery negative terminal, and removing the intake manifold, high pressure pump cover, fuel rail cover and fuel joint pipe. Never reuse the old fuel joint pipe. With P0420 or P0430 stored alongside P219A or P219B, the bulletin also calls for new injectors, and one version updates the PGM-FI software first.

A crowfoot-type tool changes the torque reading, so recalculate the wrench setting if you use one.

What if the obvious fix does not work?

Start with the mistakes that undo an injector job: replacing fewer than all the injectors, reusing the old fuel joint pipe, and skipping the PCM reset after a compression test. Also make sure no code from the first diagnosis step is still stored.

If the swap check does not follow the injector, you have already been through valve clearance, compression, the EGR line and the manifold carbon. Check the engine for oil leaks. Stop when the swap check stays clean and the engine has no oil leak. That is an intermittent fault, so try to reproduce it under the conditions recorded in the snapshot. On a van that qualifies by VIN, Honda's bulletin still calls for new injectors for these codes without the swap test, so a clean swap does not change that.

How do you confirm the repair?

Clear the codes, then warm the engine as before. Drive in 4th gear at a steady 1,000 to 1,200 rpm, then take 10 to 15 seconds to accelerate up to 3,200 rpm. If the monitor has not finished, repeat the pattern, five times in total, and only where traffic rules and conditions allow. Then read the OBD status for P219A and P219B (PASSED is what you want) or run the Cylinder A/F Test three times with A/C and loads off (OK is what you want).

If you replaced injectors, check for fuel leaks and run an all-DTC check, clearing codes from all systems. That is required, and so is the PCM reset after a compression test. Make sure none of the first-step codes have returned. On a 9-speed (Q5NZ) van that got the software update version of the repair, also confirm the transmission software is current.