Faulty fuel pressure sensor or fuel rail pressure sensor sending inaccurate data; Clogged or restricted fuel filter; Weak or failing fuel pump, leading to low fuel pressure; Leaking or stuck fuel injector; Air leaks in the intake system after the mass airflow sensor; Wiring or connector issues at the fuel pressure sensor or injectors; Faulty fuel pressure regulator (on return-style systems)

DTC codes / P01xx · Fuel and air metering / P0148

P0148Fuel Delivery Error

Q: What does code P0148 mean?

Fuel Delivery Error. P0148 is a generic powertrain code that indicates the engine control module (ECM) has detected a fuel delivery error, meaning the actual fuel quantity delivered to the engine does not match the commanded amount within an acceptable tolerance. The ECM monitors fuel pressure, injector pulse width, and other inputs to calculate this discrepancy, often using a fuel rail pressure sensor or wideband oxygen sensor feedback.

P0148 is a generic powertrain code that indicates the engine control module (ECM) has detected a fuel delivery error, meaning the actual fuel quantity delivered to the engine does not match the commanded amount within an acceptable tolerance. The ECM monitors fuel pressure, injector pulse width, and other inputs to calculate this discrepancy, often using a fuel rail pressure sensor or wideband oxygen sensor feedback.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
Rough idle or engine stumble, especially when cold
Hesitation or lack of power during acceleration
Decreased fuel economy
Difficulty starting or extended cranking
Possible misfire or engine surge under load

Common causes, most likely first

Faulty fuel pressure sensor or fuel rail pressure sensor sending inaccurate data
Clogged or restricted fuel filter
Weak or failing fuel pump, leading to low fuel pressure
Leaking or stuck fuel injector
Air leaks in the intake system after the mass airflow sensor
Wiring or connector issues at the fuel pressure sensor or injectors
Faulty fuel pressure regulator (on return-style systems)

How to diagnose and fix it

Scan all modules for stored and pending codes, and record freeze-frame data to understand when the fault occurs
Check fuel pressure with a mechanical gauge and compare to manufacturer specifications
Inspect fuel pressure sensor wiring and connectors for corrosion or damage
Test the fuel pressure sensor signal with a multimeter or scan tool to verify it tracks pressure changes
Perform a fuel injector balance test or inspect injectors for leaks or clogs
Check for intake air leaks using a smoke machine or propane enrichment
If all else checks out, reprogram or replace the ECM as a last resort

Fuel delivery error misdiagnosis traps

A P0148 can be set by a faulty fuel pressure sensor even when actual fuel pressure is correct, so always verify pressure mechanically before replacing the pump.
Some vehicles use a fuel pressure sensor that is integrated into the fuel pump module, and a failing sensor can mimic a weak pump.
Intermittent wiring faults at the fuel pressure sensor connector often cause this code without any driveability symptoms.
A clogged fuel filter may not set a lean code first; P0148 can be the earliest sign of restricted flow.
On direct-injection engines, a failing high-pressure fuel pump can set P0148 without triggering misfire codes initially.

Can I keep driving with P0148?

You can usually drive with P0148, but avoid hard acceleration and towing until diagnosed, as fuel delivery errors can worsen and lead to lean conditions or stalling. If the engine runs rough or loses power, limit driving to reach a repair shop safely.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.