I know how disappointing it is to see that the catalyst monitor is not ready after doing everything right. If the monitor is not ready, the chances of passing the smog test are lower. And without passing the test, you cannot drive your beloved vehicle.
The good news is that if your car is gasoline-powered and was manufactured in 1999 or before, one of the monitors (including the catalyst monitor) could remain incomplete. As for the models from 2000 and later, the same law applies with the exception that it cannot be an EVAP monitor.
All right, enough about the catalyst monitor. Are you even familiar with it? If not, let me share some insights.

What is a Catalyst Monitor?
The catalytic converter of the exhaust transforms toxins into less harmful substances, such as CO2 and water vapor. A catalyst monitor ensures that the converter is performing conversions as necessary. You will experience lackluster acceleration, poor engine performance, and dark exhaust smoke if the conversion stops.
More often than not, catalyst monitors are accurate. They solely rely on the O2 sensors of the car, which rarely give incorrect readings. However, just because the monitor is not running does not mean your vehicle is malfunctioning.
You have to meet certain conditions to make the device work. In the next section, I will explain what they are.
What Causes Catalyst Monitor Not Ready?
There are only a handful of reasons why the catalyst monitor might not be working. Let’s see them.
Drive Cycle
If you have not driven your ‘driving cycle’, the monitor will not be complete. The driving cycle, also known as the driving pattern, refers to a series of driving instructions that must be followed for the monitor to function. Every car has a unique drive cycle based on its manufacturer, model, and year.
O2 or AF Sensors
Another reason why the catalyst monitor is not ready is poorly performing oxygen sensors. Okay, I hear you when you say your O2 sensors seem to work perfectly. What you should know is that they may still function well and even PASS while having various issues. Replacing them is the only way to resolve this.
Gear Position Sensor
I apologize if this sounds a little crazy; your gear position sensor may be at fault for the catalyst monitor not being ready. If it malfunctions or requires replacement, the car will not appear in drive mode, even when driving at 60 mph. In that case, the monitor won’t run without indicating that the issue is with the gear position sensor.
Engine Control Unit
I stated earlier that the monitor could be incomplete due to a lack of the drive cycle. However, it is possible that you have driven the cycle, but the monitor is still not working. This may occur when the monitor cannot read the drive cycle data because the engine control unit (ECU) is blocking it.
How to Get a Catalyst Monitor Ready?
What if I told you that your monitor could be ready in just a few minutes? Sounds incredible, doesn’t it? Let me show you how it is done.
STEP – 1: Taking Precautions
While I understand that you are eager to have the catalyst monitor ready, keeping the vehicle safe during this process should be a higher priority. Therefore, you should park your car in a well-ventilated area.
The cooling system needs to be at the right level, and there needs to be enough oil in the car. Moreover, set an auxiliary fan in front of the radiator if it tends to overheat.
STEP – 2: Warming up the Vehicle
Start your vehicle and let it sit idle for around 7 minutes. This will warm up the engine slightly. Check the temperature gauge continuously to ensure it is not overheating.
STEP – 3: Keeping a steady RPM
Once the system has warmed up, hold the gas pedal and steadily increase the RPM to 3000. Continue holding the gas pedal down for 3 minutes straight at 3000 RPM.
STEP – 4: Testing the Monitor
After 3 minutes, you are free to let go of the gas pedal. Now would be the time to check the catalyst monitor, and I hope you find it to your satisfaction that it is FINALLY ready.
Can I Pass CA Smog with EVAP Monitor Not Ready?
You can pass the smog inspection even if the EVAP monitor is not working as long as the car is from 1999 or older. There is, however, a bitter twist to the new law.
Gas-powered vehicles manufactured in or after 2000 are no longer permitted to pass the smog test when the EVAP monitor is not completed. The law does allow you to leave one monitor incomplete, but it must not be the EVAP system monitor.
To Sum Up
You can obviously pass a smog test even though the catalyst monitor indicates that it is not ready. However, it gets a little trickier when it comes to the EVAP monitor.
The best thing you can do is adjust your vehicle accordingly to ensure both monitors work. In this way, you will be in compliance with the law and keep your car in good condition.