P2020 Code Definition
A P2020 code is a generic powertrain code related to the fuel and air metering and auxiliary emissions control systems. The Intake Manifold Runner Control (IMRC) controls are utilized to change or control airflow in the engine’s air intake system. If a P2020 code appears, it means the engine control module (ECM) has found a problem with the intake manifold runner control circuit in the engine’s bank 2 (or number 2 cylinder).
A P2020 code is related to:
- P2014: Intake Manifold Runner Position Sensor/Switch Circuit Bank 1
- P2015: Intake Manifold Runner Position Sensor / Switch Circuit Range / Performance Bank 1
- P2016: Intake Manifold Runner Position Sensor/Switch Circuit Low Bank 1
- P2017: Intake Manifold Runner Position Sensor/Switch Circuit High Bank 1
- P2018: Intake Manifold Runner Position Sensor/Switch Circuit Interm Bank 1
- P2019: Intake Manifold Runner Position Sensor/Switch Circuit Bank 2
- P2021: Intake Manifold Runner Position Sensor/Switch Circuit Low Bank 2
- P2022: Intake Manifold Runner Position Sensor/Switch Circuit High Bank 2
- P2023: Intake Manifold Runner Position Sensor/Switch Circuit Interm Bank 2
- P0172: System too Rich Bank 1
- P2046: Reductant Temperature Sensor Circuit Intermittent
What the P2020 Code Means
The P2020 code appears when bank 2 (the engine bank with the number 2 cylinder) is receiving a voltage reading showing that the intake manifold runner flaps are out of position, or voltage or resistance readings from the solenoid are varying outside of allowed parameters.
A vehicle’s ECM utilizes several sensor readings to determine the position of the intake manifold runners to create air turbulence in the intake manifold. If the ECM does not detect the correct manifold air pressure variation, a P2020 code will be stored.
What Causes the P2020 Code?
The P2020 code can be caused by a number of potential problems, including:
- Damaged or defective IMRC solenoid
- Carbon deposits on the manifold runner flaps
- Sticking or faulty throttle plates
- Damaged or defective IMRC valves, actuators or sensors in bank 2
- Damaged or defective ECM (rare)
What are the Symptoms of the P2020 Code?
The symptoms of a P2020 code may include:
- Check Engine Light or warning light may be illuminated
- Vibrations coming from the engine
- Fluctuations in RPM at idle (or rough idle)
- Hesitation at vehicle acceleration
- Decreased fuel efficiency
How Does a Mechanic Diagnose the P2020 Code?
A mechanic will use a variety of methods to diagnose a P2020 code including:
- Utilize an OBD-II scanner to check for a P2020 code stored in the ECM
- Visually inspect all wires and connectors for damage
- Visually inspect all hoses and vacuum lines for damage or leaks
- Test the voltage signals between the IMRC solenoid and the ECM
- Check and test that the IMRC valve moves
- Remove the IMRC and check for any damage
- Test the movement of the plates/valve for binding or looseness
Common Mistakes when Diagnosing the P2020 Code
One common mistake when diagnosing a P2020 code includes replacing the incorrect parts, such as a runner flap when the solenoid is the problem. Follow the proper procedures for correct diagnosis.
In addition, ensure you first diagnose any other intake/engine performance-related codes and check for any leaks before proceeding to diagnose a P2020, as a leak can cause the air/fuel ratio to present the incorrect possibility of a lean running engine.
How Serious is the P2020 Code?
Because mechanical failures in the IMRC can cause engine failure, this is considered a serious code. It is recommended to have your vehicle diagnosed and repaired immediately when this code appears.
What Repairs can Fix the P2020 Code?
- Repair or replace any damaged, frayed, shorted, or burned wiring
- Clean or replace any damaged connectors
- Replace any damaged plates or valves
- Replace a damaged or defective IMRC solenoid
- Replace any damaged or defective IMRC sensors or actuators
- Replace any damaged or defective runner flaps or components
- Test all system circuits (continuity and resistance)
- Replace or repair the IMRC
- Clear the code, test drive the vehicle, and rescan to see if they reappear
Additional Comments for Consideration Regarding the P2020 Code
Some manufacturers have issued technical service bulletins (TSBs) regarding the P2020 fault code, so it is recommended to always check for any associated bulletins before making any repairs.
Need Help with a P2020 Code?
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