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Q: My car shows P0172 but the car is running fine

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i have a code p0172 but mi car runs good i do not see any problem except the engine light, i change spark plugs, map sensor, air charge temperature sensor, fuel regulator, air filter, and the ecm. o2 sensors, catalitic what do you thing should be the problem?

My car has 150000 miles.
My car has an automatic transmission.

Hi there. As you already know, replacing components without diagnoses, can be expensive and time consuming without resolution. The P0172 code is an indication of too much fuel or not enough air is being delivered to the engine. The ECM (engine control module) has recognized the fault and attempts to lean the air/fuel mixture via the fuel trim. The MAF (mass airflow) sensor could be incorrectly calculating the incoming air to the engine. The evaporative emissions system may be, continuously pulling fuel vapors due to a faulty evaporative purge solenoid and/or faulty evaporative vent solenoid. I recommend having your vehicle’s Check Engine Light be diagnosed and repaired by a certified technician, such as one from YourMechanic.

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