P3451 code meaning
Cylinder 7 Deactivation/Intake Valve Control Circuit Low
Powertrain system Generic code P34xx codes Check engine light
What P3451 means
P3451 means the switched ground line of the cylinder 7 deactivation solenoid has contact with ground somewhere along its way. GM documents the check for the L84 and L86 trucks and the LT4 Corvette (2019): with the driver off, less than 0.5 ohm to ground, 20 hits in 25 samples taken every 250 ms, Type B, meaning the warning lamp waits for a second faulty trip. According to GM, certain controllers log the open-circuit code P3449 along with it, so both codes together need not mean two faults. On the L84 the high-side feed of the same solenoid reports a ground short under its own code P3117. P3452 is the short to power on this channel, P3450 the mechanical fault.
P3451 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P3451
- Check engine lamp on after two trips
- P3449 may be stored as well
- No four-cylinder mode, higher fuel use
Common causes of P3451
- Most likelyCylinder 7 control wire pinched or chafed to ground
- PossibleCylinder 7 solenoid shorted internally
- Less likelyOil or water inside the solenoid connector
- Less likelyDefective driver in the engine control module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Cylinder deactivation solenoidWiring harnessECM
What each part of P3451 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 3 | Mixed range: generic and manufacturer-specific codes. |
| 4 | Area: auxiliary emission controls (catalytic converter, EGR, EVAP). |
| 51 | The exact fault in that area. |
What to do next
- Note P3451 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P3451
What does P3451 mean?
P3451 means "Cylinder 7 Deactivation/Intake Valve Control Circuit Low". P3451 means the switched ground line of the cylinder 7 deactivation solenoid has contact with ground somewhere along its way. It is a generic code, so it means the same on every make.
Is it safe to drive with P3451?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P3451 fail an emissions test?
Yes, it can. P3451 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P3451 to fix?
Difficulty: medium. A typical repair takes 0.5 to 4 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P3451 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.