What does it mean?
P3402 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Cylinder 1 Deactivation/Intake Valve Control Circuit Performance . This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.
Symptoms
- Malfunction indicator lamp on, often after the engine has warmed up
- Brief misfire or stumble as the engine enters or leaves cylinder deactivation mode
- Tapping or ticking noise from the valvetrain, loudest at idle
- Rough idle and hesitation under light load
- Poorer fuel economy because the module disables the economy mode
- Symptoms are often worse with hot, thin oil
Likely causes
- Low oil pressure, low oil level or oil that is too thick or too thin for the system
- Oil sludge restricting the control passage or the manifold screen
- Deactivation lifter sticking so it does not lock and unlock cleanly
- High resistance in the control circuit slowing the solenoid response
- Worn solenoid that no longer moves through its full travel
- Overdue oil service leaving varnish on the control valve
- Mechanical wear in the lifter bore or camshaft lobe
How to fix it
- Verify oil level, grade and service interval; use only the viscosity specified for the engine
- Measure actual oil pressure at idle and at raised rpm and compare with specification
- Compare the commanded deactivation state with the feedback in live data
- Check solenoid resistance and perform a voltage-drop test on the control and ground circuits
- Remove and inspect the oil control manifold screens and clean or replace as needed
- Replace the solenoid if it is slow or sticking, and change the oil and filter at the same time
- Inspect the lifter and camshaft lobe if the fault returns after the hydraulic side is corrected