What exactly does “catalytic monitor incomplete” mean? Well, think of it like a check-up for your catalytic converter.
Your car’s onboard diagnostic (OBD) system is constantly monitoring the converter to make sure it’s working properly. But, if the OBD system can’t gather enough information to make a proper diagnosis, it’ll mark the catalytic monitor as “incomplete”.
Here’s a deep dive into the causes of this error message:
1. Disconnected Cells or Sensors
First and foremost, one of the major causes could be disconnected cells or sensors. These cells and sensors are responsible for monitoring the converter’s performance.
If they’re not connected, the OBD system won’t be able to gather enough information to make a proper diagnosis. So, if you suspect something like this, it’s best to have a professional take a look.
2. Code Removal Via Scan Tool
Another common cause is when someone removes stored codes via a scan tool. This could happen if someone tries to cheat the system by removing any stored codes that indicate a problem with the converter.
This is a sneaky way to avoid any issues that the converter might be having, but it also prevents the OBD system from giving an accurate diagnosis.
3. Adding Performance Tunes to Your Car’s Audio System
Moving on, one other cause could be the installation of performance tunes via an automotive spare tuner instrument.
This type of modification alters the car’s engine management system and can affect the OBD system’s ability to monitor the converter’s performance.
So, if you’re thinking about making any performance upgrades, be sure to check if it’s compatible with your catalytic converter and won’t affect the OBD system.
4. Using a Simulator to Deceive the System
Lastly, deceiving the system via a simulator installation is also a possible cause. This is when someone installs a device that simulates the presence of a catalytic converter, when in fact the converter is not present or not working properly.
This is a sneaky way to avoid issues but also illegal in some places, so it’s best to avoid it altogether.
It’s important to keep in mind that any unauthorized modification or tampering with the vehicle’s emission systems could void the warranty and also could be illegal in some places, so it’s best to avoid them.
Signs of an Incomplete Catalyst Monitor
1. Poor Acceleration and Decreased Gas Mileage
If you notice that your vehicle is struggling to accelerate or that the engine seems less efficient, it could be a sign that there’s an issue with the catalytic converter.
The converter plays an important role in the vehicle’s emissions control system, and if it’s not functioning properly, it could affect the engine’s performance.
2. Poorly Functioning Exhaust Systems and Rattling Sounds
Another sign to look out for is if you notice any issues with the exhaust system, such as reduced capacity or rattling sounds.
This could indicate a problem with the catalytic converter, which could affect the performance of the exhaust system.
3. Sulfur-Like Odors in the Car and Decreased Fuel Efficiency
If you notice any sulfur-like odors coming from the vehicle’s exhaust, it could be an indication that there’s a problem with the catalytic converter.
Additionally, if you notice that your fuel economy has decreased, it could also be a sign of a problem with the converter.
4. Illuminated Check Engine Light
If the check engine light comes on, it’s an indication that there’s an issue with the vehicle. The OBD system uses sensors to monitor the converter’s performance, and if it detects a problem, it will trigger the check engine light.
5. Broken Fuel Vapors
Another sign to look out for is broken fuel vapors. If your catalytic converter has a problem, it can cause the fuel vapors to be released into the atmosphere.
This will cause your vehicle to lose power and also will increase the number of pollutants that are released into the environment.
Read: Black Soot from Exhaust
How to Fix a “Catalytic Monitor Incomplete” Problem
1. Make Sure That the “Check Engine” Light Is Not On
Before you begin, make sure that the engine warning light is not on. The engine warning light is an indicator that there is a problem with your vehicle and it needs to be addressed.
If it is on, it could indicate a different problem with the vehicle such as a malfunctioning sensor, low oil pressure, or a problem with the emissions system, and should be addressed before attempting to set the catalytic monitor.
2. Monitor the Coolant Temperature
Before starting the drive cycle, make sure the coolant temperature is at the normal operating level. The catalytic converter needs to reach a certain temperature to function properly.
If the coolant temperature is too low, the converter may not reach the necessary temperature, and the OBD system won’t be able to gather enough information to give an accurate diagnosis.
3. Let the Engine Run Idle for 2 Minutes
Once the engine is running, let it idle for 2 minutes to allow the catalytic converter to reach operating temperature.
This step is important because the catalytic converter needs to reach a certain temperature to function properly.
4. Operate the car at a Constant 55Mph
Next, drive the vehicle at a steady speed of 55 mph for at least 15 minutes. This will help the OBD system gather enough information to give an accurate diagnosis.
During this step, try to maintain a steady speed and avoid any sudden accelerations or decelerations, as this can affect the converter’s performance and the OBD system’s ability to gather information.
5. Reduce Your Speed by 20Mph
After 15 minutes of driving at a constant speed, reduce your speed by 20 mph. This step simulates a deceleration and allows the OBD system to gather more information about the converter’s performance during this type of driving condition.
6. Continue Accelerating
Next, accelerate the vehicle as quickly as possible without exceeding the speed limit, and then return to a steady speed of 55 mph.
This step simulates an acceleration and allows the OBD system to gather more information about the converter’s performance during this type of driving condition.
7. Stop the Car
After completing the above steps, stop the vehicle and turn off the engine. The catalytic monitor should now be set and you should have a proper diagnosis.
If the problem persists after trying these steps, it’s best to have your vehicle checked by a professional mechanic to diagnose and repair any issues with the converter or other related components.
Note: It’s important to note that the drive cycle may vary depending on the make and model of your vehicle, so it’s best to check the owner’s manual for the recommended drive cycle or consult with a professional mechanic.
Conclusion
We’ve talked about the importance of catalytic converters in keeping our cars from polluting the environment and how the catalytic monitor helps us keep an eye on the converter’s performance.
We also discussed some common causes of an incomplete catalytic monitor, like disconnected cells or sensors, code removal via scan tool, using a simulator to deceive the system, and adding performance tunes to your car’s audio system.
But don’t worry, there are steps you can take to troubleshoot and fix the problem.
Signs that may indicate an issue with the catalytic monitor are poor acceleration, bad fuel economy, and strange smells or noises from the exhaust.
Remember, keeping your catalytic converter in good shape is not only important for the environment but also for your car’s performance.
And last but not least, it’s important to avoid any unauthorized modification or tampering with your vehicle’s emission systems as it could void the warranty and also could be illegal in some places.