Diagnosing Drivability and Engine Performance Issue on Mitsubishi P0123 P0222

Contents

In this guide, we will show you how to diagnose and repair possible driveability and engine performance problems on a 2019 Mitsubishi Outlander. Engine problems are typically something you would like to fix right away, it is not recommended to drive under these conditions, it could leave you stranded or cause serious damage to the engine.

The Outlander we are working on in the video is surging at idle, it also has hesitation when pushing the throttle. There are multiple malfunction indicator lamps on the dash including check engine, traction control, and stability control even though they are not related, they are triggered by this issue.

A few common causes of engine driveability problems:

  • Faulty mass airflow sensor
  • Vacuum leaks 
  • A bad emissions control system
  • Faulty fuel pump or fuel regulator
  • Leaky or sticking fuel injectors 
  • Clogged or dirty intake

As you can see there are many causes of engine driveability and performance issues.

That is why it is important to diagnose the problem before starting to make any repairs. In this guide, we will show you how to do that and help you to understand exactly how these problems occur.

This repair will require electrical repair knowledge. It is a challenging repair that might be quite difficult for most people. To avoid wasting money or time, it is not recommended to attempt this repair unless you are capable of diagnosing the issue.

What you will need

Tools

Parts

Procedure

  1. First, start by using an OBDII scan tool to read the diagnostic trouble codes (DTCs) from the vehicle's computer.
  2. Here we can see we have multiple trouble codes relating to throttle position. We have a P0123 and P0222. This tells us the problem is related to the throttle system and that the throttle position sensor voltage is not operating within a normal range. This tells us there could be an open or short anywhere inside the circuit that the throttle position sensor is part of, and this circuit has various other parts, that is why it is very important to test and check everything.
  3. It is ideal to go into a further diagnosis to tell if it is the components or the wiring causing the problem.
  4. Further diagnosis can be done by giving the connectors to the throttle a quick wiggle (called a wiggle test) while it is running to see if it changes.
  5. It is important to also do a visual check of all the wiring and components, look for anything burnt, any wires cut or broken, and any corrosion inside the electrical connectors and sensors.
  6. Testing the wiring involves quite a bit of electrical automotive repair knowledge, including knowing how to use a digital multimeter and reading wiring diagrams. You will need to make sure the wiring is carrying the correct voltages and the throttle position sensor is outputting voltages within its normal operating range. The only way to get access to this information is through repair manuals online or through the dealer which is usually paid for.
  7. If you are uncomfortable attempting this repair it is a good idea to take the vehicle to a mechanic. It is never a good idea to attempt repairs with new parts if you are not sure of what is causing the issue.
  8. If your vehicle is having the same symptoms as ours and everything visually checks out, it is likely that the throttle position sensor is the bad component. In our case, that was the issue and it was replaced and the throttle relearn procedure was done with a scan tool.
  9. We were able to confidently tell that this was the issue due to the symptoms and specific trouble codes happening. With it also being a newer vehicle it was less likely to be anything else causing the issue. However, this is not always the case and varies from each individual vehicle. Use your best judgement and always do a full diagnosis when an issue such as this comes up.

Diagnostic Trouble Codes

  • P0123 Throttle/Pedal Position Sensor Switch 'A' Circuit High
  • P0222 Throttle/Pedal Position Sensor Switch 'A' Circuit Low

Vehicle Applications

Make: Mitsubishi

Most/ All models including Outlander, Outlander Sport, Eclipse, Endeavor, Galant, Lancer, Mirage, Montero

Years: 90s, 00s, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, and 2021

 

DIY Cost: $40
Est. Time: 15 min. - 1+ hrs.
Difficulty: Difficult
Diagnosing Drivability and Engine Performance Issue on Mitsubishi P0123 P0222 In this guide, we will show you how to diagnose and repair possible driveability and engine performance problems on a 2019 Mitsubishi Outlander.