Diagnosing Drivability and Engine Performance Issue on Mitsubishi P0123 P0222

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. This guide provides instructions on diagnosing and repairing possible driveability and engine performance problems on a 2019 Mitsubishi Outlander.

In the video, we are working on an Outlander that surges at idle and has hesitation when pushing the throttle. Even though the check engine, traction control, and stability control lights are unrelated, 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 diagnosing the problem before making any repairs is important. This guide will show you how to do that and help you 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, attempting this repair is not recommended unless you can diagnose the issue.

What you will need

Tools

• Professional OBDII scan tool (must have a scan tool capable of programming the computer to relearn the throttle position)
• Digital Multimeter

Parts

• Mitsubishi throttle position sensor

Procedure

1. First, use an OBDII scan tool to read the diagnostic trouble codes (DTCs) from the vehicle’s computer.
2. Here, we see multiple trouble codes relating to throttle position. We have 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, which is why it is very important to test and check everything.
3. It is ideal to go into a further diagnosis to determine whether the components or the wiring is causing the problem.
4. Further diagnosis can be made by giving the connectors to the throttle a quick wiggle (called a wiggle test) while it is running to see if it changes.
5. A visual inspection of all the wiring and components is also crucial. Look for burns, broken wires, and corrosion inside electrical connectors and sensors.
6. Testing the wiring requires electrical automotive repair knowledge, including using a digital multimeter and reading wiring diagrams. You must ensure the wiring carries the correct voltages and the throttle position sensor is outputting voltages within its normal operating range. The only way to access this information is through repair manuals online or through the dealer, usually paid for.
7. If you are uncomfortable attempting this repair, taking the vehicle to a mechanic is a good idea. It is never a good idea to attempt repairs with new parts if you are unsure what is causing the issue.
8. If your vehicle has the same symptoms as ours and everything visually checks out, the throttle position sensor is likely 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 could confidently tell this was the issue due to the symptoms and specific trouble codes. 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 vehicle. Use your best judgment and always make 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 include Outlander, Sport, Eclipse, Endeavor, Galant, Lancer, Mirage, Montero Years: 90s, 00s, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, and 2021.

The YOUCANIC Full System Scanner can read and clear codes from all the systems in your vehicle. This powerful scanner can also perform bi-directional tests, perform maintenance and repair resets, and many more.

We hope you find the Diagnosing Drivability and Engine Performance Issue on Mitsubishi P0123 P0222 guide helpful. Check these troubleshooting and repair guides for more help on your Mitsubishi.