1998 Subaru Forester BaseFACTORY OEM SERVICE PROCEDURE

DTC P1440 (PCV_Flow): Fuel Tank Pressure Control System Function Problem Low Input

  1. Turn ignition off. Connect test mode connector behind left side of dash. Turn ignition on. Listen for clicking sound from pressure control solenoid. On 2.2L Impreza, pressure control solenoid is located underneath right rear corner of vehicle. On all other models, pressure control solenoid is located underneath vehicle, close to right front of fuel tank. If clicking sound is heard, go to next step. If clicking sound is not heard, replace pressure control solenoid.
  2. Turn ignition off. Check fuel filler cap for tightness. Check for damaged or broken seal in fuel filler cap. Replace as necessary. If fuel filler cap is okay, go to next step.
  3. Turn ignition on. Listen for clicking sound from vent control solenoid (underneath right rear corner of vehicle). If clicking sound is present, go to next step. If clicking sound is not present, replace vent control solenoid.
  4. Listen for clicking sound from purge control solenoid (under intake runner). If clicking sound is heard, go to next step. If clicking sound is not heard, replace purge control solenoid.
  5. Turn ignition off. Check for leaking fuel lines or fuel tank, damage to canister or leaking or plugged evaporative system hoses. Repair or replace as necessary.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.

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