P2594 code meaning
Turbocharger Speed Sensor B Circuit Range/Performance
Powertrain system Generic code P25xx codes Check engine light
What P2594 means
P2594 means the second turbocharger speed sensor produces a signal, but its reported speed does not agree with what the engine computer predicts for that turbo. Bentley documents it on the W12 in the Continental GT/GTC, Flying Spur and Bentayga (bulletin 2053348, versions 5 and 10): after a smoke test of intake and exhaust, a detached divider inside the air filter box on Continental and Flying Spur turned out to be one cause; with symptom code 23179 alone the code is cleared and retested without parts, while symptom code 32790 leads to a new speed sensor. P2593 and P2595-P2597 are circuit faults of the same sensor, P2579 the matching fault on sensor A. The warning lamp comes on.
P2594 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 8 hours
- Clears after repairAfter a drive cycle
Symptoms of P2594
- Malfunction indicator lamp on
- Fault often appears only under particular load or gradient conditions
- Turbo speeds of both banks differ noticeably in live data
Common causes of P2594
- Most likelySpeed sensor B delivering an implausible signal
- PossibleDetached divider in the air filter box disturbing the flow to one turbo
- PossibleIntake or exhaust leak on the bank of the second turbo
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Turbo speed sensor bTurbocharger
What each part of P2594 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 5 | Area: vehicle speed, idle control and auxiliary inputs. |
| 94 | The exact fault in that area. |
What to do next
- Note P2594 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 P2594
What does P2594 mean?
P2594 means "Turbocharger Speed Sensor B Circuit Range/Performance". P2594 means the second turbocharger speed sensor produces a signal, but its reported speed does not agree with what the engine computer predicts for that turbo. It is a generic code, so it means the same on every make.
Is it safe to drive with P2594?
Drive gently and only to a workshop. With P2594 the car can go into limp mode (reduced power) to protect itself.
Will P2594 fail an emissions test?
Yes, it can. P2594 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 P2594 to fix?
Difficulty: hard. A typical repair takes 0.5 to 8 hours of work. This is a job for a workshop.
Will P2594 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.