P3425Cylinder 4 Deactivation/Intake Valve Control Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- Cylinder 4 is one of the four cylinders that classic V8 cylinder deactivation shuts off, together with 1, 6 and 7, both at GM (Active Fuel Management) and on the Chrysler 5.7 L Hemi with MDS. That makes P3425 one of the best documented codes in this range. GM's 2019 tables for the L84 and L86 flag an open when the off-state output shows more than 200 kohm, 20 of 25 samples, Type B. Chrysler lists it as Cylinder 4 Deactivation Control Circuit; a STAR case describes the driver-side exhaust manifold heat shield wearing through the solenoid harness and asks for at least 15 mm clearance. P3427 and P3428 cover shorts on the same circuit.
- What you may notice
- Check engine lamp on
- Engine stays in eight-cylinder mode
- Further circuit codes for cylinders 1, 6 and 7 if the shared harness is damaged
- Likely causes
- LikelySolenoid harness chafed through by the exhaust manifold heat shield (5.7 L Hemi)
- PossibleOpen coil in the cylinder 4 deactivation solenoid
- PossibleCorroded or loose solenoid connector
- RareControl module software needing an update (Chrysler TSB 18-002-25)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €60 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.