Severity: ModerateHonda

P3400 on Honda Vehicles: Cylinder Deactivation System Bank 1

Cylinder shut-off on bank 1 (AFM, DFM, MDS or VCM) isn't doing what the engine computer commands. P3400 →

22Complaints mentioning the code

#1Rank among 3 brands

3.0%Share of Honda DTC complaints

In NHTSA owner complaints we analyzed for Honda, P3400 was mentioned 22 times.

Notes by brand

On Honda V6 engines with VCM (Odyssey, Pilot, Accord V6), the system is known for causing oil consumption and fouled spark plugs on the rear bank. Keeping the oil level topped up and the plugs fresh reduces VCM faults.

Most mentioned models

Honda Odyssey		11
Honda Accord Crosstour		6
Honda Pilot		3
Honda Accord		1
Honda Accord V6		1

Model years mentioned

2008: 4 · 2009: 1 · 2010: 8 · 2011: 2 · 2012: 2 · 2013: 1 · 2014: 1 · 2015: 1 · 2016: 2

Components named in these complaints

Engine (20)
Power Train (5)
Unknown Or Other (3)
Steering (1)
Fuel/propulsion System (1)

Often appears together with

P0301 Powertrain Cylinder 1 is repeatedly failing to fire. The cause is almost always its coil, plug, injector… Moderate

Possible causes

Low engine oil level, overdue oil change or wrong viscosity26%
Low oil pressure: worn oil pump, clogged pickup screen, faulty oil pressure sensor18%
Clogged screens on the lifter oil manifold or solenoid oil ports16%
Deactivation lifter stuck or collapsed, often with a damaged cam lobe16%

P3400: Diagnosis step by step →

Source: NHTSA Complaints API (US government open data), analyzed by DTC mention.