Do you own a Chevy Trailblazer? There is a possibility that you may come across the diagnostic trouble code (DTC) P2440. What do you need to know about the P2440 Chevy Trailblazer, and what steps can you take? Let’s find out.
The P2440 code means ‘secondary air injection system switching valve stuck open.’ This component is in charge of directing fresh air to the exhaust fumes. That air reduces harmful exhaust gasses through oxidation.
Let’s Break Down Code P2440 in Detail
This code has to do with your Chevy’s emission system. A secondary air injection pump draws air into the car’s exhaust system, reducing emissions released into the environment. This error code means that the secondary air injection system switching valve is stuck in an open position. This system is in charge of forcing ambient air into the exhaust system, particularly in cold starts.
The Powertrain Control Module (PCM) is the component that receives details via a voltage signal on flow and pressure from the secondary air injection system. When the PCM receives a problematic code, your Check Engine Light will come on. That means it has received a voltage read that exceeds the manufacturer’s specification by 10%.
What Are the Possible Causes of Code P2440?
Here are some of the possible causes for this diagnostic trouble code.
Faulty Air Injection Pump
According to HowStuffWorks, a secondary air injection pump is a critical component that helps reduce your vehicle’s carbon footprint. But just like other mechanical components in a car, it is prone to wear and tear or failure. And when this happens, you are likely to get the code P2440. You may also get other warning signs of your car like engine stalls, sluggish acceleration, and low idle.
The Air Injection Valve Is Faulty
Your chevy trailblazer has a secondary air injection system, which transports air to the exhaust system while preventing exhaust emissions from being released into the atmosphere. This helps improve gas mileage and reduce pollution. The air injection valve is what regulates this process. But just like any other electrical component, it can fail too. When that happens, your car will not pass the emission testing, and the Check Engine Light will come on. And while you can continue driving your car in such a condition, you don’t want to be one of those people releasing harmful pollutants to the environment. See your mechanic for assistance.
The Fuel Pressure Sensor Is Bad
Another reason you might get the P2440 DTC is when there is something wrong with the fuel pressure sensor. Your car’s fuel management system consists of several modules and sensors, including the fuel pressure sensor. When it is faulty or fails, it will significantly affect the car’s ability to supply the engine with the correct amount of fuel. Symptoms of a bad fuel sensor include poor fuel economy, difficulty starting the car, stalling, and weak acceleration.
Most car owners wonder if driving with a faulty fuel pressure sensor is okay. Well, if the issue is not too bad, you can still drive your car. However, we suggest not doing so. The longer you allow the problem to go on, the worse it gets. Let a mechanic handle the issue for you.
The Vacuum Hose Is Clogged or Disconnected
Another possible cause of the P2440 code is an issue with your vacuum hose. A combustion engine allows pressure to build up inside the contained component. To relieve this pressure and expel fumes correctly, vacuum hoses are required. But these are mechanical components subjected to gunk, high heat, dirt, debris, and any other factors that can contribute to wear and tear or damage.
When the vacuum hose is clogged, disconnected, or leaking, it will lead to multiple mechanical failures like engine misfires and full system shutdown. Mechanics usually suggest you have the vacuum hoses inspected when taking the car for servicing. This allows them to check their condition and advise you accordingly. But sometimes that does not happen, and by the time you notice the problem, it is too late.
Faulty vacuum hoses will give you several signs that you should watch out for. They include:
- The engine does not run as smoothly as before
- Check Engine Light comes on
- Engine backfires
- The engine will not start or loses power
Should I Be Worried About the P2440 Code?
When this diagnostic code is stored by the Powertrain Control Module (PCM), your vehicle will hesitate or stall out on the road. Driving under these conditions is dangerous as you can get into an accident and injure other people. Because of this, you need to be concerned about this code. Visit a mechanic who will diagnose why you are getting the code and fix it.
What Are the Common Symptoms of the P2440 Code?
Like any other diagnostic trouble code, this will also activate the Check Engine light. But aside from that, other symptoms include:
- Engines stall when starting
- Engine stalls when idling
- Unusual noises from the air injection system
- The engine hesitates when accelerating
How to Diagnose This Problem
Mechanics will start by using an OBD-II scanner to diagnose this code before trying to find the possible cause. They will then check the vacuum switching valve wirings for signs of frays, breakage, or shorts. They will also check the vacuum switching valve connectors for corrosion, bent pins, or damage.
After fixing the issues mentioned above with replacement or repairs, they will clean all the diagnostic codes from the PCM and take the vehicles on a test drive. This is to check if the code will come back.
After that, they will check the pressure sensor wiring for frays, breakage, and shorts, then check the pressure sensor connector for signs of bent pins, corroded pins, or damage. Once they fix the issues, they will again clear the code and take the vehicle for a test drive.
The same process is repeated with the one-way check valve and the air injection pump. In a way, it is like eliminating all the possible causes of the code P2440. Depending on the problem they find, they will advise you on whether you need replacement parts or repairs will do.
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Meet our senior writer and content manager of Automasterx. He has worked in several mechanical garages and mastered different vehicle diagnoses and parts repair. He never stops until finding out the ultimate solutions for any vehicle fault code. However, ensuring the only solid solutions for each vehicle malfunction is his core part of the duty, alongside analyzing fault codes and signals.