P3449Cylinder 7 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
- P3449 tells you the engine computer lost continuity in the circuit to the cylinder 7 deactivation solenoid. Chrysler documents it twice for the 5.7 L Hemi with MDS: a 2025 bulletin for the 2023 RAM 1500 eTorque lists it next to a cylinder 7 misfire (P0307) and fixes it with new PCM software, and a STAR case names P3449 first when the driver-side manifold heat shield has worn through the MDS harness at the rear of the cylinder head. GM uses the code on AFM V8s (L86, LT4 Corvette) and on the DFM L84, flagging more than 200 kohm in the off state, 20 of 25 samples, Type B. P3451 and P3452 report shorts, P3450 a mechanical fault on cylinder 7.
- What you may notice
- Check engine lamp on
- Engine stays in eight-cylinder mode
- Rough idle or misfire on cylinder 7 (P0307) on the 5.7 L Hemi
- Likely causes
- LikelyMDS harness at the rear of the driver-side head worn through by the manifold heat shield (5.7 L Hemi)
- PossibleCylinder 7 solenoid coil open
- PossibleSolenoid connector loose or corroded
- RarePCM calibration 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.