P1731 Insufficient Engine Speed Decrease During Self Test

How to Diagnose and Solve P1731 Insufficient Engine Speed Decrease During Self Test Issues


Are you a car enthusiast who loves to get your hands dirty? Or perhaps you’re a DIYer who prefers to solve car problems on your own? If so, you’ve come to the right place. Today, we’re going to delve into the nitty-gritty of diagnosing and solving P1731 Insufficient Engine Speed Decrease During Self Test issues.

Understanding P1731 Code

Before we dive into the solution, let’s first understand what the P1731 code means. This code is a generic powertrain code related to the transmission or gear box. It indicates that the engine speed is not decreasing as it should during a self-test.

What Triggers P1731 Code?

The P1731 code is triggered when the Powertrain Control Module (PCM) detects a problem with the engine speed. This could be due to a variety of reasons, such as a faulty sensor, a malfunctioning transmission, or even a software issue.

Diagnosing P1731 Code

Now that we know what the P1731 code means, let’s move on to diagnosing the issue.

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Step 1: Use an OBD-II Scanner

The first step in diagnosing a P1731 code is to use an OBD-II scanner. This device can read the trouble codes stored in your car’s computer and provide you with a detailed diagnosis.

Step 2: Check the Transmission Fluid

Next, check the transmission fluid. If it’s low or dirty, it could be causing the P1731 code.

Step 3: Inspect the Sensors

Inspect the sensors related to the transmission and engine speed. If any of them are faulty, they could be triggering the P1731 code.

Solving P1731 Code

Once you’ve diagnosed the problem, it’s time to solve it.

Step 1: Replace the Faulty Sensor

If a faulty sensor is causing the P1731 code, replace it. This is a relatively simple task that you can do yourself with the right tools.

Step 2: Change the Transmission Fluid

If the transmission fluid is the culprit, change it. This will ensure that your transmission is working properly and prevent the P1731 code from reoccurring.

Step 3: Update the Software

If the problem is due to a software issue, update the software. This can be done by a professional or, in some cases, you can do it yourself.


In conclusion, diagnosing and solving P1731 Insufficient Engine Speed Decrease During Self Test issues can be a bit challenging, but with the right knowledge and tools, it’s definitely doable. Remember, the key is to understand what the P1731 code means, diagnose the problem accurately, and then take the necessary steps to solve it.


1. Can I drive my car with a P1731 code?

While it’s possible to drive with a P1731 code, it’s not recommended. The issue could cause further damage to your car if not addressed promptly.

2. How much does it cost to fix a P1731 code?

The cost to fix a P1731 code can vary greatly depending on the cause of the problem. It could range from a few dollars for a sensor replacement to several hundred dollars for a transmission repair.

3. Can I fix a P1731 code myself?

Yes, with the right tools and knowledge, you can diagnose and fix a P1731 code yourself. However, if you’re not comfortable doing it yourself, it’s best to take your car to a professional.