P1391 FORD Possible Causes
- Faulty glow plug relay
- Faulty glow plug shunt
- Faulty glow plugs
- Glow plugs harness is open or shorted
- Glow plugs circuit poor electrical connection
- Faulty Powertrain Control Module (PCM)
First diagnose P1391 FORD code
Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded terminals.
P1391 FORD Tech NotesCalifornia trucks it has a GPCM (Glow Plug Control Module) instead of a GPR (Glow Plug Relay).
Cost of diagnosing the P1391 FORD code
Labor: 1.0The cost of diagnosing the P1391 FORD code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
P1391 FORD Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P1391 FORD MeaningThe glow plug system is monitored when the glow plugs are commanded on for more than 35 seconds and battery voltage is between 11.5-14 volts.
P1391 FORD More InformationNeed more information on how to fix the P1391 FORD code?
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