P01FF code meaning
Turbocharger Outlet Pressure Sensor A/B Correlation
Powertrain system Generic code P01xx codes Check engine light
What P01FF means
Turbocharger outlet pressure sensor B is a second pressure sensor at a compressor outlet – for example one per turbo on twin-turbo engines or a second measuring point; sensor A has the codes P00F8–P00FC. It is a separate family from the boost pressure sensor: GM and Ford report the pressure ahead of the throttle under the boost sensor codes P0236–P0238. No manufacturer using the sensor B codes was found; FCA documents sensor A and a second outlet sensor. P01FF compares sensors A and B: with the engine off both should read barometric pressure, and in comparable operation they must agree within a tolerance. If they disagree without either being electrically faulty, this code sets; which one is wrong is found by comparing with barometric and manifold pressure. On twin-turbo engines a genuinely weaker turbo on one bank can also cause it.
P01FF at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2 hours
- Clears after repairAfter a drive cycle
Symptoms of P01FF
- Check engine light on
- Loss of power, boost limited
- Limp mode possible
Common causes of P01FF
- Most likelyOne sensor drifting
- PossibleLeak or hose damage between the measuring points or on one bank
- PossibleContact resistance at one sensor's connector or ground
- Less likelyUneven turbo output (twin-turbo, wastegate or vanes on one side)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Turbocharger outlet pressure sensor aTurbocharger outlet pressure sensor bCharge air hoses
What each part of P01FF means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 1 | Area: fuel and air metering. |
| FF | The exact fault in that area. |
What to do next
- Note P01FF 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 P01FF
What does P01FF mean?
P01FF means "Turbocharger Outlet Pressure Sensor A/B Correlation". Turbocharger outlet pressure sensor B is a second pressure sensor at a compressor outlet – for example one per turbo on twin-turbo engines or a second measuring point; sensor A has the codes P00F8–P00FC. It is a generic code, so it means the same on every make.
Is it safe to drive with P01FF?
Drive gently and only to a workshop. With P01FF the car can go into limp mode (reduced power) to protect itself.
Will P01FF fail an emissions test?
Yes, it can. P01FF 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 P01FF to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P01FF clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.