P2DEA: Cylinder 1 Intake Valve Lift Range/Performance

What it means

The variable intake valve lift on cylinder 1 does not reach the commanded position within tolerance. Mechanism wear or actuator force degraded.

At a glance

• Usually lights the check-engine light
• Affects emissions; the car can fail an emissions test
• The engine or gearbox may go into limp mode

How it works

The variable intake valve lift mechanism changes how far the intake valve on cylinder 1 opens, while a position signal lets the control module compare actual lift with its command. This range/performance code sets when cylinder 1's mechanism does not reach the commanded position within the allowed tolerance.

Common causes

Most likely first.

1. Variable lift mechanism worn
2. Oil pressure to actuator low
3. Sensor element aged beyond calibration window

Symptoms

• Check-engine light
• Rough idle or misfire
• Reduced power or acceleration
• Poor fuel economy

How to diagnose it

1. Record freeze-frame data and check misfire counts and live valve-lift command and position for cylinder 1 to see when the mismatch occurs.
2. Check the engine oil level and condition, since inadequate oil supply can reduce force at the variable-lift actuator.
3. Inspect the cylinder 1 lift actuator's connector and wiring for damage, poor contact, or oil contamination.
4. Use the manufacturer's scan-tool procedure to command changes in cylinder 1 intake lift and compare the position response.
5. If the electrical checks pass, test oil supply to the actuator and inspect the cylinder 1 lift mechanism and position sensor according to service information.

Common fixes

• Correct low or unsuitable engine oil using the vehicle's specified oil and level-check procedure.
• Repair poor connections or damaged wiring at the cylinder 1 lift actuator or position sensor.
• Replace a position sensor if it fails the manufacturer's response test.
• Repair or replace the worn cylinder 1 variable-lift mechanism or actuator if inspection confirms mechanical wear or weak actuation.

Can I keep driving?

Limit driving and avoid hard acceleration because cylinder 1 may misfire and the engine may have reduced power. Stop if the check-engine light flashes or the engine runs severely rough, as continued misfiring can damage the catalytic converter.