Error P0312 – how to fix?

Hi!,this day. In this article you will find a description of fuses and relays Error P0312 – how to fix?

Include with images of block diagrams as well as their locations. Highlighted the cigarette lighter fuse (as the most common thing people look for).
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Error code definition P0312

Error code P0312 definition is that cylinder # 12 has failed.

What does the code P0312 mean

The work of any car engine is based on the use of cylinders. Each of these cylinders requires a spark plug located at the top of the cylinder. These spark plugs light up one after the other to ignite the mixture of air and fuel that is essential to the operation of the vehicle’s engine.

Once ignited, the mixture produces energy which then drives the crankshaft. The cylinders rotate by regulating the rotation of the crankshaft. Sequential ignition allows smooth rotation of the crankshaft and smooth running of the vehicle on the road.

Sometimes a fire breaks out in one of the cylinders. In this case, the RPM of the crankshaft may increase or decrease. There is a predetermined RPM range that the manufacturer has found suitable for the vehicle in question. If the crankshaft rotates 2% above or below this range as a result of an interruption of fire, the PCM (Powertrain Control Module) will record a fault code. On a 12 cylinder engine, when the misfire cylinder is # 12, the code that is recorded is P0312.

What causes the code P0312?

  • The simplest diagnosis and by far the most common reason P0312 be kept is that something is wrong with your spark plug. It may be completely broken, or it may be contaminated in some way.
  • It could also be a lack of compression in that cylinder. This would lead to a lack of rotation as there would not be so much power.

Other common causes include

  • Blown valves
  • Faulty fuel injectors
  • Poor timing of ignition
  • Vacuum leak
  • Faulty crankshaft sensor
  • Faulty camshaft sensor
  • Faulty mass air flow (MAF) sensor
  • Problems with the catalyst
  • While this is rare, it is possible that the PCM is malfunctioning. If that were the case, however, the following symptoms would most likely not occur.

What are the symptoms of the P0312 code?

As with many trouble codes, P0312 will illuminate the Check Engine light. If the RPM increases above or below the range by 10%, the indicator light will come on. However, the big difference is that you can make the light blink with this code. This happens when the rotation is outside the allowable range of 10%. This means cylinder # 12 fails to ignite because it is not getting a spark from its spark plug – a much more serious problem.

Other symptoms include:

  • Engine has difficulty starting.
  • Motor hesitates or runs erratically
  • Difficulty accelerating the engine

How can a mechanic diagnose the P0312 code?

The mechanic will start by using the OBD-II scanner to find out what trouble codes have been written by the PCM. Then he will inspect the engine components. This would include cylinder # 12, its spark plug, wiring, and connectors. After making the necessary repairs and replacements, perform a test drive with the scanner connected and working.

The most common errors when diagnosing the P0312 code

The most common mistake is when the mechanic simply replaces the spark plug and assumes that this is enough. As can be deduced from the above, the P0312 code can also represent a number of other problems, so even if the spark plug was defective, thorough diagnosis must be performed.

How serious is the P0312 code?

This is definitely code that should be taken seriously. Some of the potential symptoms listed above may make driving unsafe. Even if the dangerous symptoms are not present, it will still be difficult to drive with this code.

What repairs can fix the P0312 code?

The following repairs are usually sufficient:

  1. Replacing a defective spark plug.
  2. Replace damaged spark plug wires
  3. Repair of damaged engine components
  4. Repair or replacement of damaged cylinder head gaskets
  5. Replace blown valves
  6. In the worst case, the engine will have to be replaced because the damage to the cylinder is so extensive.

Additional notes to note for code P0312

Always replace spark plugs in pairs. However, the code P0312 usually means the rest of the vehicle may also need servicing, so it is probably best to get it done in the near future.

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