Maximizing Efficiency: How to Check Injector Balance Rates

The Duramax engines have been reliable for more than 20 years. The best way to keep your Duramax fuel system well functioning is with the use of high-quality fuel with additives. Regular fuel, air, and oil filter replacement are necessary. If there is a problem with the fuel system, it is usually connected to the injector rates.

So how to check the injector balance rates? There are two best ways – you can test it with the help of a scan tool and software or by checking the fuel pressure gauge with the scan tool. The balance rates should not be higher or lower than -/+ 4. If the value is on the minus side, the engine is using less fuel. If the value is in the plus, it is using more fuel.

If you want to test the injector balance rates, you must know how to use the tools. Also, you need to prepare the truck and the engine. Reading the results is not easy, so stay with us until the end of the article.

Understanding Injector Balance Rates

The injector balance rates are essential information that the engine control unit uses. With that info, the ECU can keep firing the injectors smoothly and evenly. That way, the engine can work quieter, more efficiently, and smoother.

When you decide to test the injector balance rates, you need to put your truck in neutral. The other option is to keep it in drive while pressing the brake. Also, the engine needs to have a working temperature. Never do this test on a cold engine.

See Also: Can You Replace Fuel Injectors Yourself?

What are Injector balance Rates?

Manufacturers of the injectors rate the injectors by the maximum amount of fuel they can flow in the given time and pressure.

How Injector Balance Rates Affect Engine Performance

Any sudden change in engine performance may point out to the poor condition of the fuel supply. Injector balance plays a major role in providing proper fuel supply, so they must be checked. Rough idling, increased fuel consumption, and white smoke coming out of the exhaust are all major issues. They are connected to the fuel system and injector flow rates.

Signs of Injector Balance Rates Issues

There are several symptoms that will point you to a problem with the injector balance rates. Also, these symptoms can point out different issues, but if you want to resolve them, don’t forget to do injector balance rate tests.

• Excess smoke coming out of the exhaust
• Drop in engine performance
• Slower acceleration
• Poor fuel economy
• Frequent engine overheating
• The diesel smell comes out when you lift the oil dipstick.

Methods for Checking Injector Balance Rates

Today, two types of injector balance tests show the most precise results. You can test the injector balance rates with the help of the scan tools and software or by using the fuel pressure gauge.

Method 1: Using Scan Tools and Software

This type of testing is the most popular today. Most mechanics have different scan tools that have the option to check injector flow rates. They can select a specific injector and measure it individually. Then they compare it with the factory values, and they can see how much the injector is off.

Method 2: Using a Fuel Pressure Gauge and Scan Tool

Using this method, the fuel pressure gauge is connected to the fuel rail pressure connection. With the help of the scan tool, it can test out individual injectors.

Check Out Duramax Balance Rate Test:

Step-by-Step Guide: Checking Injector Balance Rates with Scan Tool and Software

This is a relatively straightforward process that demands follow-through steps.

Preparation

Drive your truck so it reaches its optimum working temperature. Park it and put it in idle. Connect the scan tool to the port. There are different scan tools and software with the option of testing the injector balance rates, so you can choose the tool you want.

Connecting Scan Tool and Software

All the scan tools are connected via an OBDII connector. It is usually located under the dashboard.

Accessing Injector Balance Rate Data

Depending on the scanner you use, the process of accessing the injector balance rate date can differ. We are using ArtiDiag 600s tool and we will show you how to access the values.

1. Start with selecting Diagnosis and then checking Auto-Search. The tool will detect the car in question
2. From there, select System selection and then Powertrain system
3. Now the larger menu opens. From the drop-down menu, go to Read data stream and then Engine data display
4. You can choose Engine Data 1, Engine Data 2, and fuel system from here. Select Engine Data 2
5. From here, you can select the injector balance rates. Select all 8 injectors 
6. You can also select Desired fuel rail pressure and Actual fuel rail pressure

Interpreting and Analyzing Data

Now, you can see the values for each injector. The ideal values are 0, but everything between + and – 4 is great. From here, you can also compare the fuel rail pressure, which is important information.

Troubleshooting Issues

However, not all bad values are connected with faulty injectors. Sometimes, the problem is in the harness or the injector pigtail. In some older Duramax engines, one bad injector can eventually lead to replacing all the injectors together.

See Also: How To Check Freon Level In Car (Signs Its Low)

Step-by-Step Guide: Checking Injector Balance Rates with Fuel Pressure Gauge and Scan Tool

Preparation

Before you check the balancing rates, you should check the spark on each cylinder. If there is no spark in the cylinder, then you have a different problem. Also, you need to check the fuel supply pressures, the fuel pump, and the condition of the fuel supply system.

Connecting Fuel Pressure Gauge and Scan Tool

1. The fuel rail pressure connection needs to be connected to the fuel pressure gauge
2. Connect the scan tool with the OBDII port. Turn the scanner on, and in the special functions, search for the fuel system. There, you should find the injector balance test.

Running Engine and Monitoring Fuel Pressure and Injector Balance Rate

1. You should prime the fuel system and then select the first injector. After the fuel pump shuts off, save the first reading of the fuel pressure
2. Use the tool to pulse the first injector. After the injector stops pulsing, record the values. These values are known as Pressure After Pulse
3. Follow this method for the rest of the injectors.

Interpreting and Analyzing Data

After the test, you need to analyze the results.

1. Get the Pressure After Pulse values for each injector. These values are known as Subtracted Values.
2. There are maximum and minimum measures for the subtracted values of each injector.
3. Now, you need to calculate the maximum difference between minimum and maximum values. You can do this by subtracting the minimum from the maximum reading
4. The maximum difference should not be more than 2.9 psi. If that is the case, the injectors are fine. If the maximum difference values are higher than 2.9 psi, select the injector with the bad values and replace it.

FAQs

Final Considerations

If you at any moment notice that your engine is stalling, having problems with acceleration, or making strange noises, check your injector balance rates. The problem can often be increased fuel consumption, excess smoke from the tailpipe, or an overheating engine.

You can drive your truck to the mechanic and let the professionals sort this out, or you can try to do something yourself. For starters, you will need a scan tool. The easiest way is to check the injectors with the scan tool that you connect with the ECU. You can also connect the fuel rail to the fuel pressure gauge and then use the scan tool to check the values.

The injector balance rate values are ideally at 0, but all the rates between + and – 4 are okay. Some engines demand changing all the injectors at once. Others allow you to replace only the problematic one. In either case, don’t leave this problem unattended. This is an expensive process; the sooner you get to it, the better.