Powertrain, generic (extended)

P2A82 Alternative Fuel Pump A Compression Stroke Valve Control Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2A82 shows the drive line to pump A's compression stroke valve at a higher level than the commanded state permits, most likely because the coil winding or its wire is broken where the valve is switched to ground, or because the line touches battery voltage and the output stage loses control of it. The solenoid then cannot move the spool into the fill position, so oil never reaches the drive side and pump A performs no compression stroke at all. Gas pressure downstream of the pump sinks faster than the controller expects, and on a single-element system the engine soon runs short of fuel. Caterpillar's patents show the spool going back to drain when the solenoid is de-energized, which is the state this fault produces. No manufacturer publishes P2A82. Measure coil resistance and feed voltage.

Likely causes

Open coil or broken wire at valve A
Control wire shorted to battery voltage
Corroded valve connector

Symptoms

  • Warning lamp on
  • Falling gas pressure and power loss
  • Engine may stall on gas with a single pump element

Repair estimate

DifficultyHardWorkshop job
Parts and labour€150–1,500
Time1–4 h

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

Parts involved

alt fuel pump a compression stroke valvewiring harnessafcm

Related codes

P2A7FP2A80P2A81P2A86P2A8A

References: law.cornell.edu, patents.google.com, patents.google.com.