P1104 – OBD-II DTC

OBD-II DTC P1104 – MAF Sensor Intermittent/ Check of all OBD-II Systems Not Complete

DTC P1104 meaning

DTC P1104 refers to an issue with the Mass Air Flow (MAF) sensor, indicating that the sensor is experiencing intermittent performance. This code suggests that the MAF sensor is not providing consistent readings to the Engine Control Module (ECM), which can lead to improper air-fuel mixture calculations. Additionally, the code may indicate that all OBD-II systems have not completed their self-checks, which is necessary for the vehicle to pass emissions testing.

DTC P1104 symptoms

Common symptoms associated with DTC P1104 may include:

• Check Engine Light illuminated
• Rough idling or stalling
• Decreased fuel efficiency
• Loss of power during acceleration
• Unusual engine noises

DTC P1104 causes

Several factors can contribute to the occurrence of DTC P1104, including:

• Faulty MAF sensor
• Dirty or contaminated MAF sensor
• Vacuum leaks in the intake system
• Wiring issues or poor connections related to the MAF sensor
• ECM software issues

DTC P1104 seriousness

DTC P1104 is considered a moderate issue. While it may not cause immediate engine failure, it can lead to poor engine performance, increased emissions, and potential damage to other engine components if not addressed. It is advisable to diagnose and repair the issue promptly to maintain optimal vehicle performance and compliance with emissions regulations.

How to diagnose DTC P1104

To diagnose DTC P1104, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1104 code.
2. Inspect the MAF sensor and its wiring for any visible damage or disconnections.
3. Check for vacuum leaks in the intake system.
4. Clean the MAF sensor using appropriate cleaning solutions.
5. Test the MAF sensor with a multimeter to ensure it is functioning within specifications.
6. Check the ECM for any software updates or faults.

How to fix DTC P1104 step-by-step instructions

To fix DTC P1104, follow these steps:

1. Disconnect the battery to ensure safety while working on the vehicle.
2. Inspect and clean the MAF sensor using a specialized MAF cleaner.
3. Check and repair any damaged wiring or connectors related to the MAF sensor.
4. Inspect the intake system for vacuum leaks and repair as necessary.
5. Reconnect the battery and clear the DTC using an OBD-II scanner.
6. Take the vehicle for a test drive to ensure the code does not return and all OBD-II systems complete their checks.

How to erase DTC P1104

To erase DTC P1104, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the option to clear or erase trouble codes on the scanner.
4. Select the option to erase the DTCs.
5. Disconnect the scanner and start the engine to verify that the code has been cleared.

Recommended tools for OBD-II diagnostics

Explore our expert picks: The Best OBD2 Scanners for 2025

Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.