F150 hard to start, stalls, rough idle

Fix F150 hard to start, stalls, rough idle

If you have a 2010-2011 Ford F150 hard to start issue or a Ford F150 rough idle and stalling along with a P1450 trouble code, usually following a gas fill-up.

What is a P1450 trouble code

A P1450 is an ENHANCED manufacturer specific trouble code that might not be read by an inexpensive code reader that can only read generic OBDII codes.

P1450 – Unable to Bleed Up Fuel Tank Vacuum

This refers to the Evaporative Emissions System. For more information on EVAP system, see this post. The EVAP system monitors the fuel vapor vacuum and pressure in the fuel tank. The system fails the test and set the P1450 trouble code when the evaporative emission (EVAP) test detects excessive fuel tank vacuum with the engine running, but not at idle.

Possible Causes of P1450

Blockages or kinks in the EVAP canister tube or EVAP purge valve outlet tube between the fuel tank, the EVAP purge valve and the EVAP canister

Fuel filler cap stuck closed, preventing vacuum relief

Capless fuel tank filler pipe damaged, preventing vacuum relief (if equipped)

Contaminated fuel vapor elbow on the EVAP canister

Restricted EVAP canister

EVAP canister vent valve stuck partially or fully closed

Plugged CV solenoid filter

EVAP purge valve stuck open

VREF circuit open in the harness near the fuel tank pressure (FTP) sensor, the FTP sensor or the powertrain control module (PCM)

Damaged FTP sensor

Most common cause of F150 hard to start, stalls, rough idle

The most common cause of F150 hard to start, rough idle and stalling is

Ford F150 canister purge valve solenoid

a bad canister purge solenoid that is stuck open, so it’s continuing to draw fuel vapor into the engine.

The canister purge valve is located directly above the fuel rail on the driver’s side of the engine. Disconnect the hoses to the canister purge valve and test for airflow. There should be NO airflow unless the solenoid is grounded. To test, jumper a ground to the white/brown wire at the solenoid. If air flows when the solenoid is ground (KEY IN RUN OR RUNNING), but you see no airflow when the solenoid isn’t ground, then the canister purge valve is operating properly. A bad canister purge valve allows airflow when NOT ground and is the most common failure point.

Fix P1450 F150 hard to start, rough idle

Replace the canister purge valve

©, Rick Muscoplat