P004F
Turbocharger/Supercharger Boost Control B Circuit Intermittent/Erratic
Forced induction (turbo/super)
Generic OBD-II
High
What it means
P004F means the "B" turbo/supercharger boost-control circuit is giving intermittent or erratic readings — the signal cuts in and out instead of staying steady. It usually points to a loose or corroded connector, chafed wiring, or a failing solenoid. Boost may surge or drop unpredictably, and the car can briefly enter a reduced-power mode.
High
Can I keep driving? Usually drivable, but boost can behave unpredictably; because it's intermittent, catch it early by checking the connector and wiring before it becomes a hard fault.
Common symptoms
What you'll notice
- Check-engine light on (may be intermittent)
- Boost that surges or drops unpredictably
- Occasional reduced-power / limp mode
- Reduced fuel economy
Common causes
Most likely first
- Loose or corroded connector at the boost-control solenoid (most common for an intermittent fault)Likely
- Chafed or intermittently shorting wiringCommon
- Failing boost-control solenoidCommon
- Poor groundLess often
- Failed ECM driver (rare)Less often
How to diagnose & fix
Work through it in order
- Scan and record freeze-frame data.
- Wiggle-test the solenoid connector and harness while watching live data for dropouts.
- Clean or repair corroded connectors and secure any chafed wiring.
- Measure the solenoid's resistance against spec.
- Replace the solenoid if its reading is erratic; consider the ECM last. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P004F?+
Generally yes, but boost may come and go, and the car can briefly drop into a reduced-power mode. Because the fault is intermittent, it's best caught early.
Can I just clear P004F?+
Clearing hides it only until the signal glitches again. Track down the loose connector or chafed wire — intermittent faults rarely stay gone on their own.
Related codes
Often seen with P004F
Read & clear P004F yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX