Wiring fault such as the signal wire shorted to the 5 volt reference or to a supply voltage; Damaged, corroded or loose sensor connector terminals; Failed pressure sensor giving a constantly high output; Blocked, split or disconnected pressure or vacuum hose feeding the sensor, giving an implausible reading; Open circuit on the sensor ground, which can pull the signal high; Fault inside the engine control unit's sensor supply or input circuit.

P1144

Pressure Sensor Circuit High Input.

Subaru
Powertrain
Manufacturer code
Medium severity

How this code is built

P: SystemPowertrain
1: Defined byThe manufacturer
1: AreaFuel and air metering
44: FaultThe specific fault in that area

What it means

On Subaru, P1144 is listed as a pressure sensor circuit high input fault. The engine control unit saw the signal voltage from a pressure sensor sit above its expected range, which usually points to a short to voltage, a wiring or connector fault, or a failed sensor. Which pressure sensor is involved depends on the model and engine, so confirm it in the manufacturer's service information before replacing parts.

Symptoms

Check engine light on
Poor or uneven running, or hesitation under load
Rough idle or hard starting
Reduced power if the car has dropped into a fallback strategy
Poor fuel economy

Possible causes

Wiring fault such as the signal wire shorted to the 5 volt reference or to a supply voltagelikely
Damaged, corroded or loose sensor connector terminalslikely
Failed pressure sensor giving a constantly high outputlikely
Blocked, split or disconnected pressure or vacuum hose feeding the sensor, giving an implausible readingpossible
Open circuit on the sensor ground, which can pull the signal highpossible
Fault inside the engine control unit's sensor supply or input circuitrare

How to diagnose

Read all stored and pending codes and note the freeze frame data, including engine load, speed and coolant temperature, to see when the fault set.
Use the manufacturer's service information to identify which pressure sensor this code refers to on that model and engine.
Inspect the sensor, its connector and the nearby wiring for damage, chafing, corrosion, water ingress or poor terminal tension.
Check any hoses or pipes connected to the sensor for splits, blockages, kinks or loose fittings.
With the ignition on, view the live sensor reading and compare it with the expected value for the conditions; it should be plausible at rest and change when pressure changes.
Measure the 5 volt reference, signal and ground at the sensor connector against the wiring diagram.
Check the signal wire for a short to voltage or the reference wire, and test wiring continuity back to the control unit with the battery disconnected as per procedure.
If wiring and supplies are good, test or substitute the sensor following the manufacturer's procedure before suspecting the control unit.

How to fix

Repair or replace the damaged wiring and clean or renew faulty connector terminals.
Replace the pressure sensor if it reads high with correct supply, ground and a sound hose.
Clear, replace or refit any blocked, split or disconnected pressure or vacuum hose.
Restore the sensor ground or reference supply if either is faulty.
Repair or replace the engine control unit only after all other causes are ruled out and the manufacturer's tests confirm it.
Clear the code after repair and road test to confirm it does not return.

Can I keep driving?

Medium severity

The car can usually be driven for a short time to get it checked, but fix it soon as running quality and economy may suffer. If it is running badly or has lost power, limit driving until it has been inspected.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.