See teh link below for a detailed explanation of this code.
Check Engine code of P0404 (EGR)
The Chevy Equinox typically uses SAE 5W-30 full synthetic engine oil, although specifications may vary by model year and engine type. It's important to consult the owner's manual for the specific recommendations for your vehicle. Additionally, some newer models may also recommend using dexos1™ Gen 2 compliant oil for optimal performance. Always check for the latest information based on your specific Equinox model.
30 SECONDS WHITOUT BATTERY
How do you reset check engine light for the 2009 Chevy trail blazer?
You cannot check the fluid level as the transmission is a sealed unit. A GM dealer can check it if you have a leak. If you have no leak then it is fine.
You must have an engine scanner to do that.
You can either bring it in to a Chevy dealer or use a programmer/tuner to reset the check engine light.
It requires an engine scanner to do that.
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A flashing check engine light is an indication of a misfire.
If the check engine light is blinking that means an engine cylinder misfire has been detected