P2DEA

Code

Generic P — Powertrain

Cylinder 1 Intake Valve Lift Range/Performance

Brand: Generic

Type: P — Powertrain

Views: UK: 23 EN: 31 RU: 22

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Page language: EN

Causes

Faulty intake valve lift actuator or solenoid
Stuck or mechanically seized variable valve lift mechanism (lifter/rocker/roller/follower)
Low oil pressure or contaminated oil affecting actuator operation
Wiring harness or connector fault to actuator/solenoid or camshaft position sensors
Camshaft position/angle sensor fault or signal loss
PCM software or internal fault (less common)

Symptoms

Malfunction Indicator Lamp (MIL) illuminated
Rough idle or vibration
Misfire or misfire code for cylinder 1 may be present
Loss of power, hesitation or poor throttle response
Reduced fuel economy
Unusual valvetrain noise (ticking or tapping)

What to check

Read and record freeze-frame and all stored codes with a scan tool
Perform live-data capture: commanded vs actual intake valve lift/position for cylinder 1 and camshaft position correlation
Check engine oil level and condition; note service interval and oil contamination
Visually inspect wiring, connectors and harness to intake actuator/solenoid and cam sensors for damage/corrosion
Check for related camshaft/crankshaft correlation codes (timing issues)
Perform a mechanical inspection: remove valve cover to inspect actuator linkage, rocker/lifter, and camshaft for damage (if applicable)

Signal parameters

Commanded intake valve lift/actuator duty (%) or position value
Measured/intake valve lift or actuator position for cylinder 1 (mm or %)
Camshaft position sensor A signal (phase) and cam/crank correlation (degrees)
Intake VVT/VVL solenoid current (mA) or voltage (V) and duty cycle (%)
Engine oil pressure (kPa or psi) and oil temperature (°C)
Engine RPM and load at time of fault (freeze frame)

Diagnostic algorithm

Retrieve freeze-frame data and note conditions (RPM, load, oil temp, commanded vs actual lift). Clear codes and attempt to reproduce.
Verify basic conditions: check engine oil level/quality and top-up or change oil if dirty or low; verify recommended oil viscosity used.
Visually inspect connectors/wiring for intake actuator/solenoid and cam position sensors; wiggle-test while observing live-data for intermittent faults.
Using a scan tool, monitor commanded vs actual intake valve lift/position and camshaft angle while varying RPM and load. Note deviations specific to cylinder 1.
Measure resistance of the intake actuator/solenoid and compare to spec. If out of range, bench-test or apply controlled voltage per procedure to confirm operation.
If solenoid appears to operate electrically but lift does not change, remove valve cover (or relevant access) and inspect actuator, rocker/lifter and cam for mechanical damage, deposits or seizure.
Check oil passages to the actuator for restriction; inspect oil control valve (OCV) screens if applicable. Replace or clean as recommended.
If cam/crank correlation is incorrect, verify timing chain/belt alignment and cam phaser operation; repair mechanical timing issues as required.
If wiring, solenoid and mechanical checks are good, consider PCM software update or swap (manufacturer procedure) or consult specific manufacturer bulletin.
After repair, clear codes and perform road test/diagnostic verification with live-data; confirm commanded and actual lift are within specified range and no reoccurrence.

Likely causes

Failed intake VVL/VVT solenoid for cylinder 1
Deposits/jamming in actuator or valve-lash mechanism preventing lift change
Restricted oil passages or low engine oil level/dirty oil preventing actuator operation
Open, short or intermittent wiring to intake actuator or its relay/fuse
Faulty camshaft position sensor or incorrect cam/crank correlation
Broken rocker arm, lifter, or cam lobe specific to cylinder 1