I have a 2014 Audi A4, and the check engine light comes on and then clears after a few days, and then repeats. I brought it to the dealer and they reported the codes returned were:Fault Code: P017700 Fuel Composition Sensor Circuit Range Performance P217700 System too lean off idle.The Audi dealer quoted me a repair of $400.00 for the part and $500.00 labor. Use the FIXD Sensor and app to diagnose P0507 yourself, see the most likely fix and cost for this code, access our Mechanic Hotline, and more. Common Reason: Code P0507 is often related to a vacuum leak. The P0507 code is triggered when the Engine Control Module (ECM) detects that the engine is idling higher than the specified idle RPM range. The check engine light on your 2023 Audi A4 will ordinarily shut itself off if the issue or code that caused it to turn on is fixed. For instance, if the cause of your check engine light coming on was a loose gas cap, if it's tightened, the light will promptly turn itself off. Again, if your catalytic converter is working correctly, and you did Generic Diagnostic Trouble Code (DTC) P0299 indicates an underboost condition regarding your car. Join us as we define the code, discuss its severity, and provide solutions. If your check engine light is flashing in your 2012 Audi A4, we highly recommend not to drive the vehicle and schedule Audi service today. Below is a list of the most common reasons your check engine light can come on: Your O2 Sensor (Oxygen Sensor) needs to be replaced. The Oxygen sensor, common as the O2 sensor, measures the amount of oxygen If your check engine light is on in your Audi A4, contact Audi Creve Coeur. Our Audi service department can help you find out what code is turning your check engine light on or inspect why your check engine light is flashing. Contact Audi Creve Coeur today! Audi A4 Check Engine Light .

audi a4 check engine light codes