P3448 code meaning
Cylinder 6 Exhaust Valve Control Circuit High
Powertrain system Generic code P34xx codes Check engine light
What P3448 means
If cylinder 6 had its own exhaust valve actuator, P3448 would report its control line shorted to battery voltage. No manufacturer documents this code publicly. A GM patent application on cylinder deactivation switches both sides through one shared hydraulic valve and only lets the exhaust valves go first, off and back on, so it shows no separate exhaust control either; GM's production V8s likewise put both lifters on one solenoid and publish only P3444 for a short to power on cylinder 6. That test, below 0.5 ohm to power with the driver switched on and 20 of 25 samples, is the reference for how such a fault would be judged. With the actuator unusable, deactivation is blocked. P3445 to P3447 are the sibling exhaust codes.
P3448 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 P3448
- Check engine lamp on
- No switch to reduced-cylinder operation
Common causes of P3448
- PossibleExhaust actuator wire touching a supply line
- PossibleShorted turns in the exhaust actuator coil of cylinder 6
- Less likelyEngine control module output stage faulty
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 P3448 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). |
| 48 | The exact fault in that area. |
What to do next
- Note P3448 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 P3448
What does P3448 mean?
P3448 means "Cylinder 6 Exhaust Valve Control Circuit High". If cylinder 6 had its own exhaust valve actuator, P3448 would report its control line shorted to battery voltage. It is a generic code, so it means the same on every make.
Is it safe to drive with P3448?
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 P3448 fail an emissions test?
Yes, it can. P3448 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 P3448 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 P3448 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.