P2E55 code meaning
Exhaust Pressure Sensor C Circuit Range/Performance
Powertrain system Generic code P2Exx codes Check engine light
What P2E55 means
P2E55 is the plausibility test of exhaust pressure sensor C: the voltage is in range, but the pressure does not suit the operating state. CARB wants such rationality faults stored apart from circuit faults. No maker documents P2E55; Ford's 2023 diesel summary shows the pattern for sensor A. With the engine stopped for at least 10 s the reading may differ from ambient pressure by no more than 15 kPa; while driving it is set against a model and may not exceed it by 500 kPa or fall 100 kPa below it. A Ford patent (US7779633) computes the pressure ahead of the turbine; a Bosch patent checks two sensors on either side of a flow restriction against a modelled pressure drop. FCA warns that real back pressure from a clogged particulate filter sets the code on Cummins diesels, so check the exhaust first.
P2E55 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P2E55
- MIL, often without noticeable driveability change
- Particulate filter or EGR codes alongside
- Reduced power if the pressure is really too high
Common causes of P2E55
- Most likelyReal back pressure from a clogged particulate filter or catalyst
- PossibleSooted or cracked sensing tube to sensor C
- PossibleSensor C offset drifted or stuck mid-range
- Less likelyExhaust leak near the measuring point
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Exhaust pressure sensor cWiring harnessECM
What each part of P2E55 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 55 | The exact fault in that area. |
What to do next
- Note P2E55 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 P2E55
What does P2E55 mean?
P2E55 means "Exhaust Pressure Sensor C Circuit Range/Performance". P2E55 is the plausibility test of exhaust pressure sensor C: the voltage is in range, but the pressure does not suit the operating state. It is a generic code, so it means the same on every make.
Is it safe to drive with P2E55?
Drive gently and only to a workshop. With P2E55 the car can go into limp mode (reduced power) to protect itself.
Will P2E55 fail an emissions test?
Yes, it can. P2E55 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 P2E55 to fix?
Difficulty: medium. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will P2E55 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.