Powertrain, generic (extended)

P2A27 Alternative Fuel Tank Shutoff Valve C Control Circuit Performance/Stuck Off

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P2A27 points to valve C: electrically commanded, yet apparently still shut. With several cylinders on one manifold, a single tank that stays isolated rarely stops the engine; the others keep supplying gas, and the fault appears as shorter range or a cylinder that never empties. Ford's 2003 bi-fuel CNG system regulates to about 724 kPa and closes its tank valve below 517 kPa, which shows how gas pressure serves as the yardstick for such checks. No manufacturer publishes P2A27 or how it is tested. Contamination, a sticking armature, too little coil voltage and a closed hand valve on that cylinder are the obvious suspects. Its electrical sister codes are P2A26, P2A28 and P2A29; P2A47 rates the tank C pressure sensor.

Likely causes

Sticking or contaminated armature in valve C
Hand valve on cylinder C closed
Coil voltage too low because of a poor feed or ground

Symptoms

  • Check engine light
  • Cylinder C never empties
  • Shorter range on gas

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–1,500
Time0.5–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

alt fuel tank shutoff valve cwiring harnessafcm

Related codes

P2A26P2A28P2A29P2A47P2A23

References: law.cornell.edu, static.nhtsa.gov, static.nhtsa.gov.