Powertrain, shared range

P3402 Cylinder 1 Deactivation/Intake Valve Control Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

This code reports that cylinder 1 does not respond as expected when the engine computer switches it off or back on, although the control circuit itself tests fine. Ford lists P3402 in its Variable Displacement Engine monitor for 2020-2023 gasoline engines: it runs continuously during deactivation, entry and exit, between 400 and 4500 rpm and once oil pressure has had about two seconds to build. GM handles the mechanical check for cylinder 1 under its own code P3498 instead. Wiring faults on the same channel set P3401, P3403 or P3404. A driver typically notices a warning lamp, a shake when the engine changes modes, or a misfire on cylinder 1.

Likely causes

Low oil level, wrong viscosity or aged oil slows the hydraulic switching
Switchable lifter or rocker of cylinder 1 sticking or not latching
Deactivation solenoid valve sticking or its oil screen blocked
Leaking solenoid seal lets control pressure bleed off

Symptoms

  • Check engine lamp on
  • Shudder or jerk when the engine enters or leaves reduced-cylinder mode
  • Misfire on cylinder 1 (P0301)
  • Cylinder deactivation no longer used, higher fuel use

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–3,500
Time0–12 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

cylinder deactivation solenoidlifterengine oil

Related codes

P3401P3403P3404P3406P3400P3498P0301

References: law.cornell.edu, fordservicecontent.com, gsi.ext.gm.com.