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P0440 Lexus Code - EVAP Code 97-05 Lexus GS300

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P0440 Lexus Code - EVAP Code 97-05 Lexus GS300

Created on: 2019-04-25

The P0440 Evap code is often triggered by nothing more than a loose or worn gas cap! Watch this 1A Auto video to see what to do!

  1. step 1 :Diagnosing the P0440 Evap Code
    • The code P0440 indicates an evaproative system failure
    • The most common cause is an unsealed gas cap
    • Remove the gas cap and inspect the rubber seal ring around the gas cap for gaps and cracks
    • Inspect the spring within the gas cap for damage or weakness
    • Inspect the gas filler neck rim for rust or gouges
    • Replace the gas cap if necessary
    • Clear the code with a scan tool
    • Test drive the car

Tools needed for replacement

  • Diagnostic Tools

    Scan Tool

Installation Video
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Hey, everyone. Sue here from 1A Auto and today I want to talk to you about emission codes aka evap codes. I have a little code reader here that we have on our website and we sell. On my 2001 Lexus here I've got the code PO440. It basically means that there's an evap leak. It doesn't say large or small but I'm going to tell you the most common problem, which I'm sure you've heard is the gas cap.

Anything over 50 K or 60 K, the average gas cap starts to fail. So basically it has an evap code which the federal government has put into effect back in '96, if not a little sooner. Basically they don't want the emissions or the vapors of your gas going into the ozone. So by that we have sensors now on our gas tank, gas caps that are actually vacuum operated and sealed.

So around 50-60 K you'll start to see the O-ring breaking down. So this rubber seal right here, you can see little notches on it. Here is our filler neck, and that gets rust ring on it sometimes or build up. So you want to make sure that's smooth. You want to make sure that your seal here is not torn or started to get pitted like this. But then there's also the dreaded spring inside here.

This is under pressure to release on certain vacuum and release vacuum solenoids that are mounted on the gas tank. So this is the most common code for this is PO440, and the most common fix is a gas cap. So if you just go to 1A Auto site, we sell the gas cap. I'm just going to put that on. Fits good. Make sure it clicks. That tells you that the seal is sealed against that filler neck. I'm going to use our little handy scanner and I'm going to clear the code and road-test it.

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Tools needed for replacement:

    Diagnostic Tools

  • Scan Tool

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