Error Code P0172: What It Means & What To Do?

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The P0172 is a generic code which starts appearing when the ECU senses that there is large amount of gasoline is present in the air fuel mixture of the engine.

The right amount of air fuel ratio of 14:7:1 is essential to maintain engine power as well as fuel economy.

The P0172 fault code would start indicating that there is large amount of gasoline detected in the exhaust gases exiting the combustion chamber. A number of instruments can be used by the ECU like mass air flow sensor, oxygen sensors as well as manifold absolute pressure to monitor the air fuel ratio of the engine.

What causes this problem with the System too Rich (Bank 1)?

• There can be a dirty mass air flow sensor overstating the amount of air entering the engine which may cause excessive fuel delivery
• Poor oxygen sensor
• A leakage in the fuel injector due to which too much fuel to enter the combustion chamber
• The fuel regulator might appear to be faulty, which may not be regulating the pressure of the going to the engine as it should
• There can be some leaks in the vacuum
• Issue of possible fault in the coolant system such as a stuck thermostat or bad coolant temperature sensor
• Spark plugs might be worn out

1. Oxygen Sensor - Everything is fine with powertrain control module and still P0172 code triggering? Then you must get your Oxygen Sensor checked.
2. Vacuum - There can be some issues with the Vacuum due to which you may see P0172 code appearing over and over again. Visit us to buy best quality Vacuum online.
3. Mass Air Flow (Maf) Sensor - A lot of issues can arise do to defective Mass Air Flow (Maf) Sensor. Did you just see P0172 code flashing? Now you know the reason why it is appearing. Get it inspected and replaced on time.
4. Powertrain Control Module - Faulty Powertrain Control Module can be the reason why P0172 code is flashing. Visit us to purchase top notch Powertrain Control Module online.
5. Manifold Absolute Pressure Sensor - It is an important auto part which needs full care. A faulty Manifold Absolute Pressure Sensor can be a reason behind the flashing up of P0172 code.
6. Fuel Pressure Regulator - OBD Code P0172 can appear because of faulty Fuel Pressure Regulator.
7. Exhaust Parts - There can be some issues with the Exhaust Parts due to which you may see P0172 code appearing over and over again. Visit us to buy best quality Exhaust Parts online.
8. Coolant Temperature Sensor - Are you facing some faults in your Coolant Temperature Sensor? Don’t worry and get them replaced or else P0172 code can turn up.
9. Fuel Injector - Common cause behind this P0172 error code can be some fault in Fuel Injector. So, it will be a good decision to replace them now.
10. Fuel Pressure Regulator - Fuel Injector is perfectly fine but still but having that trouble code P0172 flashing? In such a situation your Fuel Pressure Regulator might be faulty. Why don’t you think of getting that replaced?
11. Spark Plug - The P0172 code can also arise due to some issues in Spark Plug. So, it is advised to replace them as soon as possible.

For us our customers are everything, and that’s why we will help you to diagnose P0172 code by mentioning some important symptoms below:

Common Symptoms

• A check engine light might set
• There can be an increase in the overall fuel consumption
• Black smoke can start emitting from the exhaust

Learn the ways with which you can correct this trouble code:

• If there is a vacuum leak, then you must repair it
• A faulty fuel injector, fuel pump, or fuel regulator should be immediately replaced
• Make sure that you replace an excessively restricted air filter
• Replacement of the thermostat or coolant temperature sensor
• You must replace the damaged spark plugs
• The oxygen sensors and mass air flow sensor should be cleaned properly

Don’t get tensed if you are still facing any of these issues as we care for our customers and that’s why we offer a good range of fuel pressure regulator, mass air flow sensor cleaner, car plug and a lot more. We are sure that now all your issues would be resolved.

• You must start your diagnosis by visually inspecting all wiring and connectors
• Search for shorted or burned wiring and replace circuitry and connectors as required
• If you find out that the system wiring, connectors, and components appear to be in normal working order, then you must connect the scanner to the diagnostic connector and record all stored trouble codes and freeze frame data
• This information can be extremely helpful in diagnosing intermittent conditions that may have contributed to this code being stored
• Now once the codes have been cleared, operate the vehicle to see if the code returns
• If the code fails to immediately return, you may have an intermittent condition
• Intermittent conditions can prove to be quite a challenge to diagnose and in extreme cases may have to be allowed to worsen before a correct diagnosis can be made. Inspect the idling engine for excessive vacuum leaks
• Keep in mind that you check the intake manifold gaskets, throttle body gasket, and the EGR valve and gaskets for vacuum leaks
• If you find out that there is no leakage in the vacuum, then obtaining a fuel pressure reading should be your next step
• If you find out that fuel pressure is below the manufacturer’s specified amount, suspect a clogged fuel filter
• If the fuel filter is free from debris, then check for proper fuel pump and fuel injector operation
• If fuel pressure is within acceptable levels, then inspect the mass air flow for the presence of debris or other contaminants on the hot wire
• You may clean the mass air flow sensor hot wire by carefully using a suitable cleaner (electronics cleaner or brake cleaner) and a cotton swab, then blowing it dry using compressed air
• You must be extremely careful when handling and cleaning the mass air flow and allow it to dry completely before re installation

Common Mistakes When Diagnosing The P0172 Code

The most common mistake which can happen while diagnosing the P0172 fault code is that the technician might not carefully inspect the coolant temperature sensor and cooling system. Now when the engine is cold, more amount of fuel is added which would help in warming it up as per the desirable temperature. If no proper signal is sent by the coolant temperature sensor, then there is a possibility that the engine ECU may assume that it is always running cold.

P0171 - System too Lean (Bank 1)

P0174 - System too Lean (Bank 2)