FAULTBASE
Error CodesASKCars
© 2025 FAULTBASE
All rights reserved.
v2.0.0 • Production
ContactPrivacyImpressum
Home/Cars/Toyota/Corolla/E170 (2013-2019)/how to fix P0174 code in Toyota Corolla E170 (2013-2019)

how to fix P0174 code in Toyota Corolla E170 (2013-2019)

Toyota Corolla E170 (2013-2019)

Error Codes
Severity: highDifficulty: mediumError Code: P01742-4 hours
4 min read
651 words

⚠️ Safety Warning

This issue requires immediate attention. If you are not experienced with automotive repairs, consult a professional mechanic. Working on critical systems can be dangerous.

Problem Statement

Learn how to diagnose and fix P0174 system too lean issue in Toyota Corolla E170 (2013-2019). Step-by-step guide with diagnostic procedures and repair instructions.

Error Code
P0174
Affected Component
Engine
Estimated Time
2-4 hours

Safety Warnings

  • ⚠Disconnect the battery before working on electrical components.
  • ⚠Allow the engine to cool down before inspecting the cooling system or fuel lines.

Symptoms

  • •Check engine light illuminated
  • •Rough idle
  • •Decreased engine performance
  • •Poor fuel economy
  • •Engine stalling during acceleration
  • •Increased emissions

Diagnostic Steps

  1. 1Scan for error codes using an OBD-II scanner to confirm P0174 and check for any related codes.
  2. 2Inspect the intake system for vacuum leaks, including hoses and gaskets.
  3. 3Check fuel pressure with a fuel pressure gauge to ensure the fuel pump and filter are functioning properly.
  4. 4Examine the Mass Air Flow (MAF) sensor for dirt or damage that could affect readings.
  5. 5Inspect the air filter for clogs or restrictions that could affect airflow.
  6. 6Verify the operation of the fuel injectors with a multimeter or by checking for proper spray pattern.

Solution

Solution

1. Preparation

  • Tools Required: OBD-II scanner, vacuum gauge, fuel pressure gauge, multimeter, basic hand tools (sockets, wrenches), cleaning supplies.
  • Disconnect the negative battery terminal to ensure safety while working.

2. Inspect and Repair Vacuum Leaks

  • Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
  • Use a smoke machine or carburetor cleaner to identify leaks by spraying around suspected areas while the engine is running.
  • Replace any damaged hoses or gaskets found during inspection.

3. Fuel System Check

  • Fuel Pressure Test:
    • Connect a fuel pressure gauge to the fuel rail.
    • Turn the ignition key to the "ON" position (do not start the engine) and check the pressure reading. It should be within the manufacturer specifications (typically around 40-50 psi).
    • If pressure is low, inspect the fuel pump and filter for clogs or failures.
  • Fuel Injector Inspection:
    • Disconnect the fuel injector connectors.
    • Use a multimeter to check the resistance of each injector, ensuring they are within the specified range (typically around 12-16 ohms). Replace any faulty injectors.

4. MAF Sensor Cleaning/Replacement

  • Remove the MAF sensor from the air intake duct.
  • Clean the MAF sensor using MAF sensor cleaner spray. Avoid touching the sensor element.
  • If cleaning does not resolve the issue, replace the MAF sensor with a new one.

5. Air Filter Replacement

  • Remove the air filter housing cover.
  • Inspect the air filter for dirt and debris.
  • Replace the air filter if it is clogged or excessively dirty.

6. Clear Codes and Test Drive

  • Reconnect the negative battery terminal.
  • Use the OBD-II scanner to clear the P0174 code.
  • Start the engine and take the vehicle for a test drive to monitor performance and check if the check engine light reappears.

Verification

After completing the repair, verify that the issue has been resolved:

  • ✓Test the affected component to ensure it functions correctly
  • ✓Check for any error codes or warning lights
  • ✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

  • •Follow the manufacturer's recommended maintenance schedule
  • •Address warning signs early before they develop into major issues
  • •Use quality parts and fluids recommended for your vehicle
  • •Keep detailed records of all repairs and maintenance

Tools & Equipment Required

  • •OBD-II scanner
  • •Vacuum gauge
  • •Fuel pressure gauge
  • •Multimeter
  • •Basic hand tools (sockets, wrenches)
  • •Cleaning supplies

Parts Required

  • •Vacuum hoses (if damaged)
  • •Fuel filter (if clogged)
  • •MAF sensor (if faulty)
  • •Air filter (if dirty)

Additional Information

Error Code
P0174
Affected Component
Engine
Estimated Time
2-4 hours
Difficulty
medium
Severity
high
Tools Required
6 items
Parts Required
4 items

Related Faults

  1. how to diagnose EPS problems in my Toyota Corolla E170 (2013-2019)

    Learn how to diagnose and fix EPS problems in Toyota Corolla E170 (2013-2019). Step-by-step guide with symptoms, diagnostic steps, and repair instructions.

    Steering5 symptoms

  2. why does my Toyota Corolla E170 (2013-2019) engine stutter when accelerating

    Learn how to diagnose and fix engine stuttering during acceleration in Toyota Corolla E170 (2013-2019). Step-by-step guide with diagnostic procedures and repair instructions.

    Engine6 symptoms

  3. why is my Toyota Corolla E170 (2013-2019) making a hissing noise

    Learn how to diagnose and fix hissing noise in Toyota Corolla E170 (2013-2019). Step-by-step guide with symptoms, diagnostic steps, and repair instructions.

    Engine5 symptoms

  4. Electrical short circuit solution Corolla

    Learn how to diagnose and fix an electrical short circuit in a Toyota Corolla E170 (2013-2019). Follow these steps to address issues like blown fuses and malfunctioning components.

    electrical system5 symptoms

  5. How to fix loss of power Toyota Corolla

    Learn how to diagnose and repair loss of power in Toyota Corolla E170 models. Follow these steps to identify and fix issues affecting engine performance.

    engine5 symptoms

  6. Check engine light on Toyota Corolla

    Learn how to diagnose and resolve check engine light issues on Toyota Corolla E170 (2013-2019) using OBD-II scanner and basic tools.

    engine, emissions system6 symptoms

Share this solution

Comments

Sign in to share your thoughts

Sign In

No comments yet

Be the first to share your thoughts

Back to Generation