P4150 code might get you pissed off if you drive a Ford vehicle, such as an Explorer, Focus, Fiesta, Fusion, Escape, and Fiesta. I know how you feel as I faced the same issue while driving my Ford Explorer. Don’t worry. I got you as this guide will cover some most common causes of the P1450 code in Ford vehicles. So, hang on with us till the end.
In Ford Focus, Explorer and Escape, P1450 means “Unable To Bleed Up Fuel Tank Vacuum”. P1450 trouble code is a manufacture-specific code that sets when the engine can’t control the amount of vacuum being applied to the fuel tank and the vacuum in the fuel tank is higher than expected during driving (not idling). The PCM of the engine monitors the fuel vapors in the fuel tank by opening and closing the EVAP purge valve. P1450 can be mainly caused by a defective purge valve when it is stuck open. Other possible causes of the P1450 code include defective EVAP canister or malfunctioning fuel tank pressure sensor.
Also Read: P0171 Code Meaning
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What Are The Symptoms of P1450?
P1450 does not interrupt driving like other trouble codes. The only noticeable symptom of the P1450 code in Ford vehicles is that the check engine light turns on. P1450 does not cause any driving performance issues like rough idling and does not affect the fuel economy of the engine.
However, some users report that due to P1450, your Ford vehicle might face issues with starting. I have stated this reason in my article on car not starting after getting gas. This happens when the purge valve is stuck open, excessive fuel vapors enter the engine cylinder. When there is excessive fuel in the air-fuel mixture, fuel will not be completely burnt, due to which the car takes several tries to start after it is refilled with the fuel.
Also, if an excessive vacuum is developed inside the EVAP system it can cause the fuel tank to collapse. So, it is important to troubleshoot the P1450 trouble code even if your vehicle is running fine.
How Does EVAP System Work in Engine?
EVAP stands for Evaporative Emission Control System. The EVAP system is a gas recovery system that helps to reduce emissions in vehicles by recapturing the fuel vapors before they escape into the environment.
EVAP system consists of the following parts
- EVAP purge valve
- Charcoal Canister
- Gas filler cap
- Fuel tank pressure sensor (FTP sensor)
- EVAP Vent valve
Let me summarize the working of this whole system:
- FTP sensor detects any leaks of fuel vapors in the EVAP system such as around a gas filler cap.
- Gas filler cap properly seals the fuel tank so that no fuel vapor escapes into the environment.
- Charcoal canister captures the fuel vapors accumulated in the fuel tank.
- EVAP vent valve is attached with the charcoal canister. It opens all the time to the atmosphere during the purging process so that air can suck into the system and carry the fuel vapors with it. Check valve only closes during the self-diagnostic of a large leak in the EVAP system.
- Lastly, the EVAP purge allows the fuel vapors from the charcoal canister to enter the throttle body. One end of the purge valve goes to the intake manifold and the other end goes to the charcoal canister. EVAP purge valve keeps on opening and closing, depending on the signals from ECM. When a certain vacuum is attained in the EVAP system and extra fuel vapors enter the throttle body through the purge valve, ECM closes the purge valve.
Here is a simple schematic of an EVAP system:
Note: To locate each component and connection of the EVAP system, you should have the owner’s manual as the location of each component of the EVAP system can be different, depending on the year, make, and model of the thisFord vehicle.
Possible Causes of P1450 Code in Ford
Here are some most common causes of the P1450 code in Ford vehicles.
1. Kinks or Bends, Crack, Debris in the Fuel Vapor Hoses/Tubes
To troubleshoot the P1450 trouble code in your Ford truck, you should first visually inspect all the connections, wires, and hoses of the EVAP system before removing and inspecting its components.
Here are the connections you must check:
- EVAP canister tube blockages or kinks
- Fuel vapor elbow on EVAP canister contaminated
- Vacuum hose from the purge valve to the engine air intake
Check if there is any debris around the fuel vapor hose and tubes to the EVAP connections. Also, check if the vacuum hose in the EVAP system is pinched, damaged, or kicked. Any bend in the hoses causes a further decrease in the pressure which creates an excessive vacuum in the EVAP system.
You can use a UV light across the car’s underside, following the system’s path from the engine section to the rear fuel tank to inspect the EVAP system connections. Any smoke oozing from the system will lighten up in the ultraviolet light.
You might also need to perform a smoke test using a smoke machine to detect any leaks in EVAP hoses before proceeding further. For this, you can go to your nearby mechanic to have a professional smoke test done for the EVAP system.
To check the dirt or debris in the hoses, blow the air through them and see if there is some restriction that requires more force.
2. EVAP Purge Valve Stuck Open
The most common cause of the P1450 code in Ford is when the EVAP purge valve is stuck open. EVAP purge valve is either located next to the throttle body of the engine or near the fuel tank under the vehicle.
EVAP purge valve is an electronic device called ‘solenoid’ that prevents harmful emissions from entering the environment. The EVAP purge valve is connected to the engine’s throttle body (air intake system).
When the EVAP purge valve opens, the vacuum forces the ambient air to pass through the canister where fuel vapors are stored. The air takes the excess fuel vapors from the canister to the air intake system so that they can be burnt with the existing air/fuel mixture in the engine cylinder. To learn more about a purge valve, you can read this guide.
- You can easily diagnose the purge valve. Perform these steps:
- Turn off the ignition switch.
- Locate purge valve with the help of EVAP system diagram in owner’s manual
- Remove the purge valve
- Take a vacuum pump tester and connect it with the port on the purge valve that goes to the intake manifold of the engine.
- If the valve is not holding the vacuum, it means it is faulty.
The following video will help you a lot.
3. Canister Vent Valve is Damaged or Stuck Closed
If the canister vent valve is stuck closed, it will also cause a P1450 code. The vent valve is responsible for providing an opening for the ambient air to suck in and carry the fuel vapors with it to the engine air intake manifold. If the vent valve is closed, no air will enter the EVAP system. As a result, there will be an excessive vacuum in the EVAP system.
The canister vent valve is under the vehicle near the fuel tank. To diagnose the canister vent valve, use OBD2 scanner tool to command the EVAP vent valve opened. If it does open, it means the vent valve is fine. If the vent valve does not open, it is either stuck closed or the wire harness plugged into the vent valve is not transferring the electric signals.
If there is no damage to the wiring harness of the vent valve, remove the vent valve from the vehicle and apply a direct current to the vent valve to see if it functions or not i.e. closes from the opened state or opens from the closed state.
I found the below video really helpful to test the vent valve and the wiring harness plugged into it. You should watch it till the end.
Another way to diagnose a canister vent valve is to connect it with the vacuum pump just as we do to test the EVAP purge valve. But for the canister vent valve, if the vacuum pump is not showing any vacuum, it means that the vent valve is healthy. If the pressure developed in the vent valve and it is being shown on the vacuum pump, it means that the vent valve is stuck closed.
Note: A vent valve holds a vacuum when it is opened.
4. Blocked or Damaged Charcoal Canister
A blocked charcoal canister can also cause a P1450 trouble code in Ford vehicles. If there is no dirt or debris in the vent valve tube and the vent valve is also working fine based upon the test performed above, chances are that the charcoal canister is blocked.
Find the charcoal canister under your Ford vehicle. Remove it, and check it for signs of damage caused by liquid fuel. The interior of a charcoal canister is filled with carbon pellets. So, after taking out the charcoal canister, shake it and see if water, liquid fuel, or loose charcoal granules fall out. If yes, it means the charcoal canister is defective.
Another way of checking a blocked charcoal canister is to connect a new rubber vacuum hose to the port of the canister that is linked with the vent valve. Blow through the other end of a vacuum and see if you feel any resistance. If yes, it means the canister is blocked and needs to be replaced. Make sure that you do not inhale through the vacuum hose. Otherwise, the trapped fuel vapors could enter your lungs.
5. Damaged Fuel Filler Cap
A fuel filler cap prevents escaping of fuel vapors after the fuel tank is filled. There is a relief function in the fuel filler cap that protects the fuel tank from venting when excessive fuel vapors pressure is present as well as allows atmospheric air to enter the fuel tank, thus providing a vacuum relief when the excessive vacuum is produced in the fuel tank.
However, after 2006, Ford stopped adding fuel filler caps in their vehicles. The Ford vehicles after 2006 have a capless fuel filler neck having a spring-loaded flap so that it is closed automatically as soon as the fuel nozzle is removed. For the capless neck, check any dirt particles or debris in the sealing area around the inlet. One way of cleaning the debris around the filler neck is to jam the funnel into the capless filler neck and spray WD-40 or blow compressed air.
6. Defective FTP Sensor
Sometimes a defective fuel tank pressure sensor can also cause P1450 trouble and turns on the check engine light if it sends wrong signals of pressure in fuel tank to the ECM. So, you should also check whether the FTP sensor is working fine or not. In most cases, the FTP sensor is mounted on the top of the fuel tank. In some vehicles, the FTP sensor is located inside the fuel tank.
First, check the connector to the FTP sensor. Disconnect the connector. Turn on the ignition. You should get 5 or so volts from the 5v gray wire to the ground (black wire) on a multimeter.
With the ignition on and the connector still disconnected from the FTP sensor, you should get a sound from the green signal wire to the black ground or good body ground.
If the wiring harness is fine, it’s time to test the FTP sensor. Turn ignition on. Connect the multimeter to the wire harness. Apply a small vacuum to the outlet port of the FTP sensor using a vacuum pump. If the voltage on the multimeter decreases while applying vacuum, it means the FTP sensor is fine.
So, that’s all about all possible causes of the P1450 code in Ford vehicles. To cut into short, you should perform the following steps to troubleshoot P1450 in your Ford vehicle:
- First, check all vacuum hoses and tubes in the EVAP system. Check for any cracks, debris, and bends.
- If everything is fine, it’s time to check the EVAP purge valve which is the most likely cause of the P1450 code.
- If the EVAP purge valve is fine, you should check the canister vent valve. Also, check any blockage in the hose connected to the vent valve.
- If the vent valve is fine, check whether the charcoal canister is blocked.
- Also, check the debris and dirt around the opening of a fuel filler neck.
- Lastly, check the FTP sensor.
I hope you would have found this guide helpful. To troubleshoot each component of the EVAP system, you should have a vacuum pump and a good quality multimeter, and some tools to remove the EVAP components. Also, consult your owner’s manual to find the correct way of removing any EVAP component.
If you need further help, you can discuss it in the comment section below.