EngineLightCodes
Powertrain code

P018D Fuel Pressure Sensor B Circuit High

Severity
Fix soon
Typical repair cost
$60–$330
Do it yourself
Possible, medium
Shop time
0.5–2 hours

Fuel pressure sensor B is a second fuel pressure sensor; which one is up to the manufacturer.

How the engine computer detects it

On GM it is the low-pressure sensor in the supply line of direct-injection engines (0–743 kPa (0–108 psi)), read by the engine module or the fuel pump control module; on Ford engines with dual injection it is the sensor on the port-injection rail (0.5–4.5 V for about 0–70 psi). Sensor A is the high-pressure rail sensor (P0190–P0194). P018D means the signal voltage is above its upper limit – usually an open sensor ground or a signal wire shorted to the 5 V reference or battery voltage. GM sets it above 96 % of the reference (about 4.8 V, equal to 743 kPa (108 psi)) or above 4.86 V when read by the fuel pump module; two trips. Ford sets it above 4.88 V for 8 s. Water ingress in the connector is a common trigger. A substitute value is used.

Written from public technical sources and not yet checked by a mechanic. How we write these pages

Symptoms

  • Check engine light on
  • Starting problems
  • Lack of power
  • Sometimes no symptoms

Common causes

  1. Sensor ground open Most likely
  2. Signal wire shorted to 5 V or battery voltage Possible
  3. Sensor faulty Possible
  4. Connector corrosion or water ingress Possible

How to diagnose P018D

  1. Read every stored code with an OBD-II scanner. If misfire or fuel trim codes are there too, fix those first: they often cause this one.
  2. Inspect the parts involved: fuel pressure sensor b, sensor wiring, sensor reference voltage.
  3. Work through the causes above from most to least likely, cheapest checks first.
  4. Clear the code and drive a full drive cycle to confirm the repair held.

Reading the code

P
Powertrain
0
Generic (SAE) code
1
Fuel and air metering
8D
Specific fault

Questions drivers ask

Can I drive with code P018D?

Usually yes for a short time, if the car drives normally, the temperature gauge reads normal and the check engine light is steady. If the light flashes, the engine loses power or overheats, or other warning lights come on, pull over and have it checked.

Will my car pass an emissions inspection with P018D?

Probably not in states that test vehicles with an OBD-II scan: an emissions-related code that keeps the check engine light on is usually an automatic fail. Rules differ by state and county, so check yours.

Will P018D clear by itself?

The light can go off after several drive cycles without the fault, but the code returns if the cause is still there. After a repair, the readiness monitors need a full drive cycle before an inspection.

Can I fix P018D myself?

Often yes, with an OBD-II scanner and basic tools. Difficulty: medium. Start with the cheapest checks before replacing expensive parts.

This page is general information, not a substitute for a professional diagnosis. Repair costs are rough estimates for parts and labor and vary by vehicle and region.