Chevy Tahoe P0446 OBDII Code Diagnosis

The most frequent trouble code with the Chevy Tahoe The Code P0446. This trouble code is the number given to you by an OBDII scanner when your Tahoe is connected. It indicates that an error has occurred in the evaporative exhaust control system. You may see it along with the following codes: P0441, P0420 and P0440.

P0446: Evaporative Emission Control System Vent Control Circuit Malfunction

The P0446 problem is not usually a serious threat to your car's driveability. Certainly anytime the service engine soon light is on, it’s good to deal with it as soon as possible though. P0442 is commonly accompanied. For more information, see Chevy Tahoe OBDII code P0442. The P0446 trouble code P0420 can also be used.

Chevy Tahoe P0446 OBDII Code Symptoms

Most commonly, the P0446 code does not cause any symptoms. You will see the light on your service engine shortly, but this is typically it. It is possible to notice an increase in fuel consumption, but it is unlikely. A slight gas smell may be caused by P0446. Because it is related to the fuel vapors system, P0446 may also cause a slight gas smell.

Chevy Tahoe P0446 Meaning

The universal OBDII code P0446 can be used to diagnose trouble codes. It means that no matter what make or model vehicle you have, this code will always mean the same thing. Technically, the code stands for:

Evaporative Emission Control System Vent Control Circuit Malfunction

The EVAP captures any fuel vapor in the fuel tank. It then transmits these to the engine intake to allow for normal combustion. If the EVAP control circuit vent control circuit does not respond to the ECU it will throw the OBDII code P0446.

Tahoe P0446 Trouble code Causes

Many things can trigger the P0446 code in Chevy Tahoe. These are some of the more common issues that can trigger the P0446 trouble code in your Chevy Tahoe:

• Vapor Canister Purge Valve– One of the most common causes of the P0446 code is the vapor canister purge valve.
• It’s really easy to replace. You will need to locate and take out a few clips.
• Hose for Evap System– The hose that carries the fuel vapor from the fuel tank to the intake manifold can begin to leak. This can lead to the code P0446. It should have a hole or tear.
• A Faulty Canister of Charcoal– The charcoal canister is often the cause of P0446.
• Fuel Tank Sending Unit– It is possible for the fuel tank sending unit to go bad. It can cause a disruption in the line pressure, throwing off the code.
• Fuel Cap– A bad fuel cap can cause the code to be thrown for sure. Often, you’ll get a message informing you that the fuel cap is off even when it is on. You may not get the message but a P0446. This will save you time and money.
• Fuel Filler Neck– There is often a gasket where the fuel filler neck connects with the gas tank. The gasket may dry out especially if the vehicle is in dry conditions. When it dries out, the fuel tank can’t hold pressure anymore.

Chevy Tahoe Diagnostics - Page 0446

To diagnose the problem with your Chevy Tahoe's P0446, a mechanic can use a variety of tools. The most commonly used methods to diagnose this code are:

• The mechanic will usually check for any additional trouble codes. It is easier to diagnose problems if there are more codes. That’s because when they appear together in certain combinations, there will often only be only a few conditions that will throw any combination of codes at one time.
• The mechanic will normally determine what trouble codes are associated with P0446. Take a look at the EVAP system. It includes the purge valve and line as well as the canister.
• A mechanic will examine the gas cap and verify that it is able to withstand high pressure. If you are getting a warning that your gas cap is off, even when it’s on, replacing it will more than likely clear this code.
• Monitor and check the pressure in your fuel tank.
• The mechanic will then perform the following tests after completing the above-mentioned checks:
• A smoke test, and they’ll use a scan tool to confirm that the EVAP solenoids and valves are operating properly.

Most common P0446 fixes

These are the top Tahoe P0446 fix ideas:

• Replacement of gas cap
• Replacement for EVAP Line
• Replace charcoal canister
• Replacing the fuel tank

You should start with the gas caps and move on to the fuel tanks. This is because the gas caps are the easiest to replace and the least costly.

Here’s a great video on How to check your gas cap.

You will need to solve the problem. This should help. You can add any additional information by leaving a comment.