Fuel and air

P018D — Fuel Pressure Sensor "B" Circuit High

Severity: medium Drive with care, to a shop

What P018D means

The engine control unit reads the voltage from fuel pressure sensor "B" to know how much pressure the fuel system is making. P018D sets when that signal goes above the expected range. The cause can be a bad sensor, an open or a short to voltage in the wiring, or truly excessive fuel pressure. With unreliable data the ECU cannot control fuel delivery accurately.

Symptoms

  • Check Engine light on
  • Hard starting or long cranking
  • Reduced power and sluggish acceleration
  • Poor fuel economy
  • Rough idle
  • Stalling
  • No-start in severe cases

Possible causes

  1. Failed fuel pressure sensor "B"
  2. Short to voltage or open circuit in the sensor wiring
  3. Poor sensor ground connection
  4. Corroded or loose sensor connector
  5. Actual fuel pressure too high (regulator or control valve fault)
  6. Faulty PCM (rare)

How to diagnose

  1. Scan for codes and freeze frame data, and note any other fuel system codes
  2. Compare specified and actual fuel pressure in live data at cranking, idle and under load
  3. Check low-pressure supply pressure and volume
  4. Inspect the sensor connector and harness for corrosion, chafing, heat damage or moisture
  5. Use a multimeter to test the 5 V reference, ground and signal wire for opens and shorts to voltage
  6. Compare the sensor reading with a mechanical gauge where the system allows it
  7. Test the pressure regulator or control valve and injector return flow where applicable
  8. If wiring checks out, replace the sensor, and suspect the PCM only after that

Common fixes

  • Replace fuel pressure sensor "B"
  • Repair the wiring or replace the damaged connector
  • Replace the pressure regulator or control valve if pressure is truly too high
  • Replace or reprogram the PCM if everything else is good

Questions and answers

What does P018D mean?

The PCM is getting too high a voltage from fuel pressure sensor "B". It may be the sensor, the wiring, or genuinely excessive fuel pressure.

Can I drive with code P018D?

Only briefly and carefully, for example to a shop. The engine may lose power or stall, which is dangerous in traffic.

How do I clear P018D?

Clearing the code only helps temporarily, since it returns until the fault is fixed. Find the cause in the sensor, wiring or fuel system first.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.