Skip to content
Diagnostic Trouble Code (DTC) P1174 indicates a problem with the fuel trim balance on a Chevy engine, usually highlighting an imbalance in the fuel mixture across the engine's cylinders.
Below, we provide a comprehensive guide on how to diagnose and resolve the P1174 code on your Chevy.
What It Means
The P1174 code signifies that the Powertrain Control Module (PCM) has detected a fuel trim imbalance.
The PCM constantly adjusts the air-fuel mixture for optimal performance and efficiency.
When it identifies that one or more cylinders are not receiving the correct fuel mixture, it triggers the P1174 code.
This imbalance could result from various factors, such as vacuum leaks, fuel injector issues, or problems with the Mass Air Flow (MAF) sensor.
Symptoms
Recognizing the symptoms associated with the P1174 code can help in diagnosing the problem more effectively.
When this code is triggered, the Check Engine Light (CEL) is typically illuminated on your dashboard, alerting you to the issue.
You might notice that the engine runs unevenly at idle, characterized by a rough or fluctuating idle speed.
This rough idle can be unsettling and is a direct result of the imbalance in the air-fuel mixture.
You may experience a noticeable decrease in fuel efficiency.
The imbalance in the fuel mixture often leads to the engine burning more fuel than necessary, reducing overall fuel economy.
Engine misfires are another common symptom, especially at low speeds or under load.
These misfires can cause the engine to run poorly and may even lead to damage if left unaddressed.
Poor acceleration is another symptom to watch out for. The vehicle may struggle to accelerate smoothly, feeling sluggish and unresponsive.
This is due to the engine not receiving the proper fuel mixture, which affects its ability to produce power efficiently.
$439.99
Diagnose Code P1174
Before attempting to fix the issue, a thorough diagnosis is essential. Here are the steps to diagnose the P1174 code:
1. Scan the PCM for Trouble Codes
Use a car scanner to read the trouble codes stored in the PCM.
Besides P1174, there might be other related codes that can provide additional clues about the problem.
2. Inspect the Vacuum System
A vacuum leak can cause an imbalance in the air-fuel mixture.
Check all vacuum hoses and connections for cracks, leaks, or disconnections.
Pay special attention to the intake manifold gasket and throttle body gasket.
Using the ANCEL S3000 automotive smoke machine can be particularly effective in identifying vacuum leaks.
This tool can quickly detect even the smallest leaks, ensuring that no potential issue is overlooked.
3. Check the Fuel Injectors
Faulty or clogged fuel injectors can lead to uneven fuel distribution. Inspect the injectors for proper operation.
If your fuel injectors are clogged, you can use the ANCEL AJ400 injector cleaning machine to remove deposits effectively.
Many automotive mechanics use this machine for its efficiency in restoring injector performance.
4. Test the Mass Air Flow (MAF) Sensor
The MAF sensor measures the amount of air entering the engine and helps the PCM adjust the fuel mixture.
A dirty or faulty MAF sensor can provide incorrect readings, leading to an imbalance.
Clean the sensor using a dedicated MAF cleaner and check for proper function.
5. Examine the Oxygen Sensors
The oxygen sensors monitor the exhaust gases and help the PCM adjust the air-fuel ratio.
Malfunctioning sensors can cause incorrect adjustments. Test the sensors and replace any that are not functioning correctly.
6. Check the Fuel Pressure
Insufficient or inconsistent fuel pressure can cause an imbalance in the fuel mixture.
Use a fuel pressure gauge to check the pressure at the fuel rail. Ensure it matches the specifications for your Chevy model.
Related Reading: What Does Ford Code P0193 Mean?
Fix Code P1174
Once you have diagnosed the problem, follow these steps to fix the P1174 code:
Repair Any Vacuum Leaks
If you found any vacuum leaks during your inspection, repair or replace the affected hoses or gaskets.
Ensure all connections are secure and free from leaks.
Clean or Replace Fuel Injectors
If the fuel injectors are dirty or faulty, clean them using a professional fuel injector cleaner or replace them if necessary.
Ensure they are delivering fuel evenly to all cylinders.
If your fuel injectors are clogged, you can use the ANCEL AJ400 injector cleaning machine to remove deposits effectively.
Many automotive mechanics use this machine for its efficiency in restoring injector performance.
Clean or Replace the MAF Sensor
A dirty MAF sensor can often be cleaned with a dedicated MAF cleaner.
If cleaning does not resolve the issue, replace the sensor with a new one to ensure accurate air measurements.
Replace Faulty Oxygen Sensors
Replace any oxygen sensors that are not functioning correctly.
Use OEM parts for the best compatibility and performance.
Adjust Fuel Pressure
If the fuel pressure is incorrect, inspect the fuel pump, fuel filter, and pressure regulator.
Replace any faulty components and ensure the fuel pressure is within the specified range.
Preventive Maintenance
To avoid future occurrences of the P1174 code, regular maintenance is essential. Here are some preventive measures:
- Regularly Inspect and Replace Air Filters: A clean air filter ensures the engine receives the proper amount of air.
- Use Quality Fuel and Additives: High-quality fuel and fuel additives can help keep the fuel system clean.
- Routine Fuel System Cleaning: Periodically use a fuel system cleaner to maintain clean injectors and fuel lines.
- Monitor and Replace Sensors as Needed: Regularly check the MAF and oxygen sensors and replace them as part of scheduled maintenance.
Conclusion
Is fixing the P1174 code on your Chevy difficult? Not really! It’s not as daunting as it might seem.
With the right tools from ANCEL, resolving automotive issues becomes much easier.
ANCEL’s automotive tools are excellent companions for tackling car problems, and they are not limited to just cars—they work great for heavy trucks and motorcycles too.
For more information, click to check out ANCEL.
FAQs
How much does it cost to fix the P1174 code?
The cost to fix the P1174 code can vary depending on the underlying cause. Repairs may range from simple sensor replacements to more extensive fuel system repairs.
How long does it take to fix the P1174 code?
The time required to fix the P1174 code depends on the complexity of the issue. Simple fixes like replacing sensors may take a few hours, while more involved repairs could take longer.
What are the risks of ignoring the P1174 code?
Ignoring the P1174 code can lead to poor engine performance, decreased fuel efficiency, and potential engine damage due to improper air-fuel mixture.
Recommended Similar Articles：
- Is P0128 a Thermostat or Sensor? We Provide Solutions
- Is Your Chevrolet's Automatic Transmission Shifting Erratically? Here's What You Need to Know
- Is the Engine Cooling Fan the Same as the Radiator Fan? No, and Here's Why
- Motor Oil Weights | What They Mean and Why They Matter
- What Does Ford Code P0193 Mean?
