How to Fix P050D? (Copy detect 20% Fix then post)

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The error code P050D is stated as the Cold Start Rough Idle error in the vehicle. It is one of the generic trouble codes, which means that all of the vehicles that are equipped with the OBD-II system might encounter this error code on a usual basis. All of the modern-day vehicles are liable to experience this trouble over time. 

When this error occurs, the PCM or the Powertrain Control Module determines the rough engine idle error during cold start conditions. Cold Start is the term that is used to state the engine’s drivability when it is at the ambient temperature or even lower than that. The purpose of PCM is to monitor the idle level of the vehicle engine. 

Hence, to do that, the intake airflow tends to be regulated during closed throttle conditions. The PCM then regulates the intake air of the engine at an idle state, with the use of an electronically controlled device called the IAC (Idle Air Control). If the air that enters the vehicle engine is unregulated, then it might result in causing a rough engine to idle during the cold start conditions. Hence, it will set the P050D error code. 

P050D Code Meaning

P050D Code Meaning

The P050D error code occurs when the air intake into the engine is unregulated! But if the malfunction occurs only during the cold start conditions, then it means that the ECT or Engine Coolant Temperature is malfunctioning gradually. The strategy for engine driveability is quite different during the cold start conditions. 

If the PCM gets an incorrect engine temperature signal during the cold start-ups, then it might lead to the rough idle. It might be due to the lack of fuel delivery and improper timing advance. The ECT Sensor Code might also get stored, and you might have to diagnose and repair the error codes related to that of the ECT sensors before you can tackle the P050D code. 

Symptoms of P050D Code

The basic symptom for the P050D and all of the other error codes is that the Check Engine light will turn on. This is the signal that there has been an error code registered for your vehicle. It is an indication that you should get your vehicle checked and get the error fixed at the earliest. But, apart from that, there are a couple of other symptoms as well that you should pay attention to! They are:

  • Lean or rich exhaust 
  • Drivability issues during cold start conditions. 
  • Sucking noise emission from the engine. At the time, you might get a hissing noise as well. 

If you are observing these symptoms in your vehicle, then park it right at the authorized service centers and get it diagnosed & fixed. Delaying upon fixing the error will deteriorate the problem and might cause permanent damage. 

Causes of P050D Code

There are certain reasons or causes that might have contributed to triggering the P050D code. Knowing these causes will give you a better idea of how you can maintain your vehicle engine in the future to avoid this error. The causes include:

  • Vacuum problems or air leaks. 
  • Insufficient fuel volume or pressure problems. 
  • Poor or damaged spark plugs, plug boots, or ignition coils might also be the critical cause. 
  • Open or shorted circuits and connectors are responsible for the P050D code. 
  • Damaged ECT sensor

How to Diagnose the P050D Code?

Here are the diagnostic measures that the technicians will take in order to determine the root cause of the P050D code:

  • If there are any other existing lean exhaust codes or IAC related codes alongside the P050D code, then it is important for you to diagnose & repair all of them first before you can approach fixing the P050D code. 
  • Engine misfire is also responsible for contributing to the trough idle that originates under the cold start conditions. If other misfire codes are triggered along with the P050D code, then fix them first. There is a possibility that fixing those codes might fix the P050D code error as well. 
  • For properly diagnosing the P050D code error, you will need a diagnostic scanner, vehicle information source, and DVOM tools. Vehicle Information Course will offer diagnostic flow charts, connector pin-out charts, wiring diagrams, component testing procedures, and connector face views. These aspects help the technicians to diagnose the error code accurately. 
  • The technicians get all of the codes stored. They record the freeze-frame data by establishing a connection of the scanner with the diagnostic port of the vehicle. They take note of the information obtained by this connection. And then, they will clear the codes to allow the engine to cool down before it can be test-driven. 
  • If the code doesn’t come back when the engine heats up again, then the problem might have been solved. If this happens, then you can conclude that the PCM has entered the readiness mode. 

Common Mistakes that you Must Avoid When Diagnosing P050D 

Here are some of the common mistakes that the technicians make during the diagnosis process of P050D code:

  • They do not check for battery drain problems.
  • They misdiagnose the PCM as ECM. 
  • They miss out on resetting the systems and clearing the codes from modules before test driving the vehicle. 
  • They do not start the vehicle with the use of a good spark plug wire, rotor, ignition coil, and distributor cap. 
  • Missing out on changing the defective parts with new ones. 

How to Fix P050D Code?

How to Fix P050D Code?

Here are the repairs that the technicians should adapt in order to fix the P050D code:

  • Repair the vacuum leaks
  • Replace the ignition coils, plug boots, and faulty spark plugs. 
  • Check for fuel levels within the tank
  • Fix all of the open or shorted connectors and circuits. 
  • Replace the ECT sensor. 

Tips for Further Avoiding the P050D Error Code

Timely maintenance is the only way to avoid this hassle over time! Apart from that, if you observe any of the symptoms for this P050D code, then you should respond immediately. It is because the Rough idle under cold start conditions might be a severe vehicle issue! Keep that in mind, and you might avoid this error for your vehicle in the future. 


These are a few of the things that you should know about the P050D code and take necessary actions when needed. Hence, this will eventually save your vehicle from permanent operational damages!