Okay, then there are no codes stored in the engine computer, below is a picture of the Idle air control valve (IAC) which your vehicle may or may not have. Its required by California emissions standards, if you do have an IAC, make sure the 2 smaller tubes which are for coolant flow are clear, don't open the cooling system when it's hot, so check this in the morning when the vehicle is cold, I will usually just clamp off the 2 hoses then remove them from the valve so no coolant is lost. But make sure they are clear, you can then unbolt the valve and check on the backside which is not visible in the this picture, but make sure it's not full of carbon build up. Being that your vehicle has an electronic throttle body, you may not have an IAC. But check the tag under the hood to see if it's a California regulated emissions standard vehicle.
If you don't have one of these valves, then start looking for a vacuum leak, check for any cracked or loose hoses.
The 2nd diagram shows the Evap (vapor) hoses that run all the way back to the gas tank, but just look for any that are broken. The VSV valve is where the system will pull vapors from the gas tank into the intake manifold to be burned. Check those hoses as well as the PCV hose for cracks, the PCV hoses tend to become brittle and break, The guide I posted previously has some methods for finding vacuum leaks. You can also take the line coming into the VSV valve and block the end to make sure it's not leaking air into the intake manifold. Let us know if you have any other questions and what you find.
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Thursday, October 12th, 2023 AT 9:04 AM