P3450Cylinder 7 Deactivation/Intake Valve Control Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P3450 reports that cylinder 7 does not deactivate or reactivate as commanded while its solenoid circuit checks out. FCA lists it as Cylinder 7 Deactivation Control Performance for the 6.4 l Heavy Duty Hemi with MDS (RAM 2500 to 5500, bulletins 18-082-16 and 18-036-20): the MIL lights and a PCM reflash cures it, with an optional calibration that also eases drone and shudder in MDS mode. On the 2025 F-150 5.0 l, Ford bulletin 26-2093, which replaces 25-2487, pairs it with P3442 and has the left-bank solenoid oil feed tube replaced under the valve cover. In GM's system, as NHTSA describes it, oil pressure moves locking pins so the lifter body travels without opening the valve. GM's L84 uses P349E. Electrical faults: P3449, P3451, P3452.
- What you may notice
- Check engine lamp on
- Ticking noise from the valve train
- Misfire on cylinder 7 (P0307)
- Reduced-cylinder mode switched off
- Likely causes
- PossibleRestricted oil feed tube to the left-bank solenoids (Ford 5.0 l, TSB 26-2093)
- PossibleOutdated PCM calibration (FCA 6.4 l, bulletins 18-082-16 and 18-036-20)
- PossibleLocking pins in a cylinder 7 lifter sticking from wear or dirt
- PossibleInsufficient or aged oil delaying the switch
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €3,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.