Powertrain, generic · Fuel and air metering

P016F Closed Loop Fuel Pressure Control At Limit - Pressure Too Low

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

Common-rail diesels regulate rail pressure in closed loop: the control module compares the rail pressure sensor with the target and adjusts a volume or pressure control valve, learning correction factors as it goes. CARB requires faults to be flagged when this feedback control does not start in time or runs out of authority. P016F means the controller is at its limit in the 'more pressure' direction and the actual pressure still stays below target. Which circuit is meant depends on the manufacturer: Volvo and Mack use it for rail pressure, for example as a follow-up when their electronic pressure relief valve stays open (P009B); on FCA's 3.0 EcoDiesel it concerns the regulated low-pressure supply via the fuel pump control module and appears with P025C and P01C6, partly fixed by new engine software. No public thresholds exist. Weak supply pumps, clogged filters and corroded connectors or grounds are typical causes.

Likely causes

Weak low-pressure supply: lift/tank pump, pump control module, clogged filter
Connector or ground problems (corrosion, water) at pump module, low-pressure sensor or ground point
Pressure relief valve open or its control circuit interrupted
Worn high-pressure pump or internal leak
Engine control module software

Symptoms

  • Check engine light on
  • Loss of power, sluggish acceleration
  • Hard starting, long cranking, stalling after start
  • Rough cold idle

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–2,000
Time1–5 h

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

Parts involved

fuel pump modulefuel filterfuel pressure control valvehigh pressure fuel pump

Related codes

P016EP016DP0087P008AP025CP009B

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