Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2021 Acura ILXFACTORY OEM SERVICE PROCEDURE
Engine Control System / Engine Mechanical - Service, Testing And Troubleshooting (Except Hybrid)
- Replacement
- Disassembly, Reassembly, and Inspection
- Check
- System Description
- Catalytic Converter - Overview (2016 2017 2018 2019 2020 2021 2022)
- Catalytic Converter - Overview(K24Z7) (2013 2014 2015)
- Catalytic Converter - Overview(R20A5) (2013 2014)
- Catalytic Converter - Overview(R20A5) (2015)
- EGR - Overview(R20A5) (2013 2014 2015)
- EVAP (KA, KC models) (2013 2014 2015)
- EVAP (KA, KC models) (2016 2017 2018 2019 2020 2021 2022)
- Electronic Throttle Control (2013 2014 2015)
- Electronic Throttle Control (2016 2017 2018 2019 2020 2021 2022)
- Intake Air System - Intake Manifold Tuning (IMT) Valve System (2016 2017 2018 2019 2020 2021 2022)
- Intake Air - Intake Manifold Tuning (IMT) Valve System(R20A5) (2013 2014 2015)
- Intake Air - Vacuum Hose Routing
- PCV - Overview (2013 2014 2015)
- PCV - Overview (2016 2017 2018 2019 2020 2021 2022)
- PGM-FI - Components (2016 2017 2018 2019 2020 2021 2022)
- PGM-FI - Components (KA, KC models K24Z7) (2013 2014 2015)
- PGM-FI - Components (KA, KC models R20A5) (2013 2014)
- PGM-FI - Components (KA, KC models R20A5) (2015)
- PGM-FI - Electronic Control (2013 2014 2015)
- PGM-FI - Electronic Control (2016 2017 2018 2019 2020 2021 2022)
- PGM-FI - Ignition Timing Control (2013 2014 2015)
- PGM-FI - Ignition Timing Control (2016 2017 2018 2019 2020 2021 2022)
- PGM-FI - Injection Control (2013 2014 2015)
- PGM-FI - Injection Control (2016 2017 2018 2019 2020 2021 2022)
- PGM-FI - OBD (2013 2014 2015)
- PGM-FI - OBD (2016 2017 2018 2019 2020 2021 2022)
- PGM-FI - On-Board Snapshot (2013 2014 2015)
- PGM-FI - On-Board Snapshot (2016 2017 2018 2019 2020 2021 2022)
- PGM-FI - Overview
- VTEC (R20A5) (2013 2014 2015)
- VTEC/VTC - Construction(K24Z7/K24V7)
- VTEC/VTC - Control(K24Z7/K24V7)
- VTEC/VTC - Operation(K24Z7/K24V7)
- VTEC/VTC System Description - Overview(K24Z7/K24V7)
- VTEC/VTC System Description - VTC (2016 2017 2018 2019 2020 2021 2022)
- VTEC/VTC System Description - VTEC (2016 2017 2018 2019 2020 2021 2022)
- Learning Reset Clear
- Component Location Index
- Catalytic Converter System (2016 2017 2018 2019 2020 2021 2022)
- Catalytic Converter System (K24Z7) (2013 2014 2015)
- Catalytic Converter System (KA, KC models R20A5) (2015)
- Catalytic Converter System (R20A5) (2013 2014 2015)
- EGR System (R20A5) (2013 2014 2015)
- EVAP Control System (K24Z7)
- EVAP Control System (KA, KC models)
- EVAP Control System (Premium.Technology)
- Electronic Throttle Control System (K24Z7/K24V7)
- Electronic Throttle Control System (R20A5) (2013 2014 2015)
- Engine Block Assembly (2016 2017 2018 2019 2020 2021 2022)
- Engine Block Assembly (K24Z7) (2013 2014 2015)
- Engine Block Assembly (R20A5) (2013 2014 2015)
- IMT System (2016 2017 2018 2019 2020 2021 2022)
- IMT System (R20A5) (2013 2014 2015)
- PCV System (2016 2017 2018 2019 2020 2021 2022)
- PCV System (K24Z7) (2013 2014 2015)
- PCV System (R20A5) (2013 2014 2015)
- PGM-FI System (K24Z7) (2013 2014 2015)
- PGM-FI System (KA, KC models R20A5) (2015 2016 2017 2018 2019 2020 2021 2022)
- PGM-FI System (R20A5) (2013 2014 2015)
- VTEC System (R20A5) (2013 2014 2015)
- VTEC/VTC System (2016 2017 2018 2019 2020 2021 2022)
- VTEC/VTC System (KA, KC models K24Z7) (2013 2014 2015)
- Connector View
- Adjustment
- Removal, Installation & Inspection
- Air Cleaner Element (2016 2017 2018 2019 2020 2021 2022)
- Air Cleaner Element (K24Z7) (2013 2014 2015)
- Air Cleaner Element (R20A5) (2013 2014 2015)
- Crankshaft and CKP Pulse Plate (2016 2017 2018 2019 2020 2021 2022)
- Crankshaft and CKP Pulse Plate (K24Z7) (2013 2014 2015)
- Crankshaft and CKP Pulse Plate (R20A5) (2013 2014 2015)
- Rewrite
- Test
- Symptom Troubleshooting Index for Viewer
- After warming up, idle speed is above specifications without load (MIL works OK, no DTCs set) (2016 2017 2018 2019 2020 2021 2022)
- After warming up, idle speed is above specifications without load (MIL works OK, no DTCs set) (KA, KC models K24Z7) (2013 2014 2015)
- After warming up, idle speed is above specifications without load (MIL works OK, no DTCs set) (KA, KC models R20A5) (2013 2014 2015)
- After warming up, idle speed is below specifications without load (MIL works OK, no DTCs set) (2016 2017 2018 2019 2020 2021 2022)
- After warming up, idle speed is below specifications without load (MIL works OK, no DTCs set) (KA, KC models K24Z7) (2013 2014 2015)
- After warming up, idle speed is below specifications without load (MIL works OK, no DTCs set) (KA, KC models R20A5) (2013 2014 2015)
- Cold fast idle too high (MIL works OK, no DTCs set) (2016 2017 2018 2019 2020 2021 2022)
- Cold fast idle too high (MIL works OK, no DTCs set) (KA, KC models K24Z7) (2013 2014 2015)
- Cold fast idle too high (MIL works OK, no DTCs set) (KA, KC models R20A5) (2013 2014 2015)
- Cold fast idle too low (MIL works OK, no DTCs set) (2016 2017 2018 2019 2020 2021 2022)
- Cold fast idle too low (MIL works OK, no DTCs set) (KA, KC models K24Z7) (2013 2014 2015)
- Cold fast idle too low (MIL works OK, no DTCs set) (KA, KC models R20A5) (2013 2014 2015)
- Difficult to refuel (MIL works OK, NO DTCs set) (KA, KC models K24Z7) (2013 2014 2015)
- Difficult to refuel (MIL works OK, no DTCs set) (2016 2017 2018 2019 2020 2021 2022)
- Difficult to refuel (MIL works OK, no DTCs set) (KA, KC models R20A5) (2013 2014 2015)
- Engine is hard to start (MIL works OK, no DTCs set) (2016 2017 2018 2019 2020 2021 2022)
- Engine is hard to start (MIL works OK, no DTCs set) (KA, KC models K24Z7) (2013 2014 2015)
- Engine is hard to start (MIL works OK, no DTCs set) (KA, KC models R20A5) (2013 2014 2015)
- Engine stalls (MIL works OK, no DTCs set) (2016 2017 2018 2019 2020 2021 2022)
- Engine stalls (MIL works OK, no DTCs set) (KA, KC models K24Z7) (2013 2014 2015)
- Engine stalls (MIL works OK, no DTCs set) (KA, KC models R20A5) (2013 2014 2015)
- Engine starts but stalls immediately (MIL works OK, no DTCs set, immobilizer indicator stays on or flashes) (2016 2017 2018 2019 2020 2021 2022)
- Engine starts but stalls immediately (MIL works OK, no DTCs set, immobilizer indicator stays on or flashes) (KA, KC models K24Z7) (2013 2014 2015)
- Engine starts but stalls immediately (MIL works OK, no DTCs set, immobilizer indicator stays on or flashes) (KA, KC models R20A5) (2013 2014 2015)
- Engine will not start (MIL works OK, no DTCs set) (2016 2017 2018 2019 2020 2021 2022)
- Engine will not start (MIL works OK, no DTCs set) (KA, KC models K24Z7) (2013 2014 2015)
- Engine will not start (MIL works OK, no DTCs set) (KA, KC models R20A5) (2013 2014 2015)
- Engine will not start (MIL works OK, no DTCs set, immobilizer indicator stays on or flashes) (2016 2017 2018 2019 2020 2021 2022)
- Engine will not start (MIL works OK, no DTCs set, immobilizer indicator stays on or flashes) (KA, KC models K24Z7) (2013 2014 2015)
- Engine will not start (MIL works OK, no DTCs set, immobilizer indicator stays on or flashes) (KA, KC models R20A5) (2013 2014 2015)
- Engine will not start and HDS does not communicate with the PCM(MIL comes on and stays on, no DTCs set) (2016 2017 2018 2019 2020 2021 2022)
- Engine will not start and HDS does not communicate with the PCM(MIL comes on and stays on, no DTCs set) (KA, KC models K24Z7) (2013 2014 2015)
- Engine will not start and HDS does not communicate with the PCM(MIL comes on and stays on, no DTCs set) (KA, KC models R20A5) (2013 2014 2015)
- HDS does not communicate with the PCM or the vehicle (2016 2017 2018 2019 2020 2021 2022)
- HDS does not communicate with the PCM or the vehicle(KA, KC models K24Z7) (2013 2014 2015)
- HDS does not communicate with the PCM or the vehicle(KA, KC models R20A5) (2013 2014 2015)
- Idle speed fluctuates (MIL works OK, no DTCs set) (2016 2017 2018 2019 2020 2021 2022)
- Idle speed fluctuates (MIL works OK, no DTCs set) (KA, KC models K24Z7) (2013 2014 2015)
- Idle speed fluctuates (MIL works OK, no DTCs set) (KA, KC models R20A5) (2013 2014 2015)
- Low power (MIL works OK, no DTCs set) (2016 2017 2018 2019 2020 2021 2022)
- Low power (MIL works OK, no DTCs set) (KA, KC models K24Z7) (2013 2014 2015)
- Low power (MIL works OK, no DTCs set) (KA, KC models R20A5) (2013 2014 2015)
- MIL comes on and stays on, or never comes on at all, no DTCs set (2016 2017 2018 2019 2020 2021 2022)
- MIL comes on and stays on, or never comes on at all, no DTCs set(KA, KC models K24Z7) (2013 2014 2015)
- MIL comes on and stays on, or never comes on at all, no DTCs set(KA, KC models R20A5) (2013 2014 2015)
- General Information
- Engine Configuration (2016 2017 2018 2019 2020 2021 2022)
- Engine Configuration(K24Z7) (2013 2014 2015)
- Engine Configuration(R20A5) (2013 2014 2015)
- How to Set Readiness Codes (2013 2014 2015)
- Malfunction Indicator Lamp (MIL) Indication (In relation to Readiness Codes)
- Catalytic Converter Monitor and Readiness Code
- Evaporative Emission (EVAP) Control System Monitor and Readiness Code
- Air Fuel Ratio (A/F) Sensor Monitor and Readiness Code
- Air Fuel Ratio (A/F) Sensor Heater Monitor Readiness Code
- Misfire Monitor and Readiness Code
- Fuel System Monitor and Readiness Code
- Comprehensive Component Monitor and Readiness Code
- EGR Monitor and Readiness Code
- How to Set Readiness Codes (2016 2017 2018 2019 2020 2021 2022)
- Malfunction Indicator Lamp (MIL) Indication (In relation to Readiness Codes)
- Catalytic Converter Monitor and Readiness Code
- Evaporative Emission (EVAP) Control System Monitor and Readiness Code
- Air Fuel Ratio (A/F) Sensor Monitor and Readiness Code
- Air Fuel Ratio (A/F) Sensor Heater Monitor Readiness Code
- Misfire Monitor and Readiness Code
- Fuel System Monitor and Readiness Code
- Comprehensive Component Monitor and Readiness Code
- EGR Monitor and Readiness Code
- Under-Hood Emission Control Label(KA, KC models) (2013)
- Under-Hood Emission Control Label(KA, KC models) (2016)
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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