P2A8F code meaning
Alternative Fuel Pump B Performance
Powertrain system Generic code P2Axx codes Check engine light
What P2A8F means
P2A8F applies to a second alternative fuel pump whose output has fallen short of expectations. Layouts with two pumps usually give each LNG vessel its own pump, a redundancy Westport's documents mention explicitly. In US20080302111A1, a selector valve decides which pump delivers, and once the controller judges one pump degraded it can switch to the other. The difficulty lies in telling a weak pump from an empty tank: Westport's US8726785B2 notes that little drive work per stroke can mean either a nearly empty vessel or a broken component such as the drive shaft. A P2A8F shortly after refuelling therefore points to the pump itself. Pump B may also be the healthy one, so check which tank was active. No manufacturer documents P2A8F or how its letter is assigned.
P2A8F at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor3 to 10 hours
- Clears after repairAfter a drive cycle
Symptoms of P2A8F
- Malfunction lamp on
- Usable range shorter, fuel left in one tank
- System changes to the other tank earlier than usual
Common causes of P2A8F
- Most likelyWorn seals reducing the delivery of pump B
- PossibleTank served by pump B almost empty, mimicking a weak pump
- Less likelyBroken drive shaft or coupling between hydraulic drive and pump B
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Alt fuel pump bAlt fuel filter
What each part of P2A8F means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| A | Area: hybrid propulsion. |
| 8F | The exact fault in that area. |
What to do next
- Note P2A8F 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 P2A8F
What does P2A8F mean?
P2A8F means "Alternative Fuel Pump B Performance". P2A8F applies to a second alternative fuel pump whose output has fallen short of expectations. It is a generic code, so it means the same on every make.
Is it safe to drive with P2A8F?
Drive gently and only to a workshop. With P2A8F the car can go into limp mode (reduced power) to protect itself.
Will P2A8F fail an emissions test?
Yes, it can. P2A8F 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 P2A8F to fix?
Difficulty: workshop only. A typical repair takes 3 to 10 hours of work. This is a job for a workshop.
Will P2A8F 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.