P043E Toyota Tundra Reasons And Solutions Explained

Are you facing problems with the P043E Toyota Tundra? It actually represents Evaporative Emission System Leak Detection Reference Orifice Low Flow.

Well, the problem is regarding the canister. It could be in any Canister component or the whole thing itself. So, if your vehicle is pretty old, to solve the P043E code issue, it’s wiser to replace the EVAP canister with a new one.

Here’s a detailed guide for knowing everything about the P043E code. So, let’s begin.

P043E Toyota Tundra Code Reasons with Resolves

First, check out the causes that can cause this error code at a glance.

Causes For P043E Toyota TundraProbable Symptoms
1. Leak in the gas tank
2. Cracked Gasket
3. Defect In The EVAP Pressure Sensor
4. Canister Is Damaged
5. Damaged Leak Detection Pump
6. Defect In Purge Control
7. Damaged Vacuum Line Or Lines
Fuel odor outside the  vehicle
Check Engine Light pops up
Running speed doesn’t get fast in acceleration
Bad Engine sounds while starting

There could be multiple reasons behind the error code P043E can occur. Firstly let’s talk about the most straightforward issue which we often don’t find out.

Leak In The Gas Tank

Sometimes, the loose gas cap can create a P043E problem. When the gas cap is loose, the vapor gets access to the environment. Then, your engine light starts to show signs. When you check with a digital meter, you see the error code P043E.

Solution: So, after diagnosis, if you see the code, check on the gas cap first. If the gas cap is not appropriately locked, lock it tightly. And you’re good to go.

Cracked Gasket

It could be the torn, dry rotted, or cracked gasket on the gas tank cap that is creating the problem. If the gas cap is cracked or broken, it passes vapor outside. That’s how your vehicle can get a P043E code problem.

Solution: Replace the old broken gas cap with a new one. You should get one that has a vacuum located on the cap if your gas tank does not have any vacuum inside the gas tank.

Defect In The EVAP Pressure Sensor

Defects in the EVAP pressure sensor can cause a negative difference in your vehicle’s performance. The main job of an EVAP pressure sensor is to measure the pressure of the fuel system to detect any evaporative leak.

When the EVAP pressure sensor is damaged, it fails at its job, eventually affecting your vehicle’s overall working capability.

Solution: To ensure your vehicle’s excellent performance, you’ve to replace the old EVAP Pressure Sensor. It’s necessary to prevent further problems.

The Canister Is Damaged

The canister is the Charcoal System of a vehicle. It’s an accommodated system that contains other significant components inside. Canister plays a vital role in lowering fuel emissions.

It stores the vapor and reduces emission. Once you start the engine, the vapors are drawn to the engine to burn. When your canister is damaged, your vehicle loses its high acceleration power. Thus, the leak detection orifice low flow occurs.

Solution: Unfortunately, canister being a considerable part of your engine system, you can’t fix the problem quickly. So, you have to replace it with a new Canister.

You can do the replacement yourself because it’s pretty easy to DIY. But make sure you buy the new canister with the exact part number.  

There are two gas tanks underneath the drive shaft, with the seat underneath the shield. The line connected to it goes to the fender that is your fuel filler.

Then, the smaller line goes from the gas tank to the EVAP Canister underneath the plastic cover. You’ve to remove the plastic cover to remove the canister.

When the canister is visible, you’ll need to remove three hoses and some electric connectors to release the canister. While removing the canister, make sure you’ve all the connections disconnected. And now you’re ready to install the new canister.

Damaged Leak Detection Pump

The Leak Detection Pump is a crucial part of the canister. It ensures your EVAP system is working appropriately. This pump helps to detect small leaks that can’t be seen.

Solution: When the Leak Detection Pump is contaminated, several issues in performance occur. So, it’s necessary to replace the part immediately.

Defect In Purge Control

The Purge Control or the Purge Valve is a valve that restricts the vapors’ emission coming out to the atmosphere. This valve forces the vapor to be stored in the canister. Damaged Purge Valve can’t do the work. So, the leak occurs.

Solution: To maintain the synced works of the whole EVAP unit, you need an excellent Purge Valve. If your one is damaged, replace it with a new Purge Valve.

Damaged Vacuum Line Or Lines

Vacuum line leakage or damage can affect the fuel and air mixture. So, the ratio of the combinations gets unbalanced, eventually decreasing the vehicle’s running performance.

Solution: Replace the damaged Vacuum lines and secure the connections correctly.

This Video Will Help You Too!

Frequently Asked Questions (FAQs)

What does code P043E mean?

The code P043E means Evaporative Emission System Leak Detection Reference Orifice Low Flow. This occurs for the issue in the canister of the vehicle.

Where is the EVAP pressure sensor located?

The EVAP pressure sensor is generally located either inside the tank or at the top of the tank. Different design newer vehicles may have the EVAP pressure sensor in a different location.

Is it OK to drive with an EVAP leak?

No, it is not OK to drive with an EVAP leak because it can lead to severe further damage. So, as soon as you notice an EVAP leak with engine light indication, visit the garage and fix the issue.


By the end of this article, we hope that now you have a clear idea about P043E Toyota Tundra. If you face the EVAP leak problem, don’t delay and check the error code to fix it early.

If your scanner tells you that your EVAP system has a P043E error code, do not drive your vehicle further with this condition. However, it’s permitted to drive with the error code for a short distance, but going for long distances with the P043E code is strictly prohibited.

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D Conroy

Meet our senior writer and content manager of Automasterx. He has worked in several mechanical garages and mastered different vehicle diagnoses and parts repair. He never stops until finding out the ultimate solutions for any vehicle fault code. However, ensuring the only solid solutions for each vehicle malfunction is his core part of the duty, alongside analyzing fault codes and signals.

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