P1181 MERCURY Possible Causes
- Restriction in fuel line
- Clogged fuel filter
- Faulty fuel pressure regulator
- Faulty fuel rail solenoid shutoff valve
- Fuel rail solenoid shutoff valve wiring harness is open or shorted
- Poor electrical connection in the fuel rail shutoff solenoid circuit
How to Fix Code P1181 MERCURY?
Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.
Possible Symptoms
- Engine light on (or engine service warning light soon)
P1181 MERCURY Meaning
The Powertrain Control Module (PCM) receives fuel tank pressure (FTP) information from the Natural Gas Module (NG), which uses this information to infer fuel rail pressure (FRP). The Diagnostic Trouble Code (DTC) is set and the test fails when the inferred pressure is below a maximum calibrated value.