Engine chock. checked with actron auto scanner and says 1 catalyst monitor incorrect 2evap system monitor incorrect 3 oxygen sense monitor incorrect 4 oxygen sense htr incorrect 5 EGR system monitor incorrect

DTC P0420: Catalyst System Low Efficiency Bank 1
Circuit/System Description
Important: A new converter with less than 100 miles on it may set DTC P0420 due to out-gassing of the internal matting. Operating the vehicle at highway speeds for approximately 1 hour may correct the condition.
A 3-way catalytic converter (TWC) controls emissions by converting hydrocarbons (HC) and carbon monoxide (CO) into carbon dioxide (CO2), and oxides of nitrogen (NOx) into nitrogen. The TWC also stores oxygen. When the listed idle conditions follow the listed driving conditions, the Catalyst System Efficiency test will run. The powertrain control module (PCM) monitors this oxygen storage capacity by comparing the pre and post-catalyst oxygen sensor signals while adding and subtracting fuel during specific idle conditions. The PCM compares the pre and post-catalyst-oxygen sensor signals to determine if the oxygen storage capacity of the catalyst is degraded.

https://www.youtube.com/watch?v=CflIvd5VOoA&t=293s

DTC P2097 Post Catalyst Fuel Trim System High Limit Bank 1
Circuit Description
The wide band heated oxygen sensor (HO2S) measures the amount of oxygen in the exhaust system and provides more information than the switching style HO2S. The wide band sensor consists of an oxygen sensing cell, an oxygen pumping cell, and a heater. The exhaust gas sample passes through a diffusion gap between the sensing cell and the pumping cell. The engine control module (ECM) supplies a voltage to the HO2S and uses this voltage as a reference to the amount of oxygen in the exhaust system. An electronic circuit within the ECM controls the pump current through the oxygen pumping cell in order to maintain a constant voltage in the oxygen sensing cell. The ECM monitors the voltage variation in the sensing cell and attempts to keep the voltage constant by increasing or decreasing the amount of current flow, or oxygen ion flow, to the pumping cell. By measuring the amount of current required to maintain the voltage in the sensing cell, the ECM can determine the concentration of oxygen in the exhaust. The HO2S voltage is displayed as a lambda value. A lambda value of 1 is equal to a stoichiometric air fuel ratio of 14.7:1. Under normal operating conditions, the lambda value will remain around 1. When the fuel system is lean, the oxygen level will be high and the lambda signal will be high or more than 1. When the fuel system is rich, the oxygen level will be low, and the lambda signal will be low or less than 1. The ECM uses this information to maintain the correct air/fuel ratio.
Fuel trim biasing is used by the ECM to keep the post catalyst HO2S voltage within a range of 580-665 mV as possible. This allows optimal catalyst efficiency under light load conditions, such as at idle or a steady cruise. The ECM constantly monitors how lean or rich the fuel trim bias is commanded. If the ECM detects that the fuel trim bias is commanded rich for more than a calibrated amount, DTC P2097 or P2099 sets.


Air Fuel Wideband vs Oxygen Sensors O2 sensors The Demise of Shadetree...

Got it scanned and it's P0420: Catalyst efficiency below thresholdbank 1. They said it could be a bad catalytic converter or oxygen sensor. I borrowed a scanner and tried to measure the oxygen sensor readings over time.Sep 8, 2011


civic - Check Engine code P0420 Catalyst efficiency below ...

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P0420 Error Code: Catalyst System Efficiency Below ...

www.obd-codes.com/p0420
P0420 OBD-II Trouble Code. Technical Description. Catalyst System Efficiency Below Threshold (Bank 1). What does that mean? This diagnostic trouble code ...

P0420 Code Fix How Its Done Catalyst Efficiency Below ...

? 4:25
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Jun 20, 2014 - Uploaded by ACE AUTOS UK
Here is a tutorial on P0420 code fix catalyst efficiency below threshold How To Diagnose a p0420 code ...

Duplicate question.

P0429 Description The Engine Control Module (ECM) monitors the switching frequency ratio of heated oxygen sensors 1 (front O2 sensor) and heated oxygen sensors 2 (rear O2 sensor).



A three way catalyst converter (Manifold) with high oxygen storage capacity will indicate a low switching frequency of heated oxygen sensor 2. As oxygen storage capacity decreases, the heated oxygen sensor 2 switching frequency will increase.



When the frequency ratio of heated oxygen sensors 1 and 2 approaches a specified limit value, the three way catalyst malfunction is diagnosed.
Possible causes - Catalyst Heater Control harness is open or shorted
- Catalyst Heater Control circuit poor electrical connection
- Faulty Powertrain Control Module

Boy you had better go back and read more about what a catalytic converter does, remember in chemistry a catalyst is a thing that facilitates a chemical reaction but is not directly involved in that reaction? Ring a bell.

P0402: Catalyst System Efficiency Below Threshold Bank 1

The ECM or PCM monitors the switching frequency ratio of heated oxygen sensors 1 and 2. A three way catalyst converter(Manifold) with high oxygen storage capacity will indicate a low switching frequency of heated oxygen sensor 2. As oxygen storage capacity decreases, the heated oxygen sensor 2 switching frequency will increase. When the frequency ratio of heated oxygen sensors 1 and 2 approaches a specified limit value, the three way catalyst (Manifold) malfunction is diagnosed.



Possible Causes:
- Three way catalyst converter Bank 2
- Exhaust tube
- Intake air leaks
- Fuel injectors may be faulty
- Fuel injector leaks
- Spark plugs may be faulty
- Improper ignition timing
- Engine Control Module

Possible Solutions:
The most common cause is the three way catalyst converter Bank 1. Changing just the O2 sensor usually doesn't repair the problem.

Diagnostic code produces P0420 catalyst system efficiency below threshold-Bank 1. Probable causes are listed as follows:
1-air leak in exhaust before rear 02 sensor, 3-Fuel system fault,
4-faulty catalytic converter.

16716/P0332 - Knock Sensor 2 (G66): Signal Too Low Possible Symptoms

• Irregular rpm
• Drivability problems
• Loss of power
• Engine damage

Possible Causes

• Circuit G66 short to Ground
• Circuit G66 open
• G66 improperly torqued
• G66 damaged
• Control Module damaged

16804/P0420/001056 - Catalyst System; Bank 1: Efficiency Below Threshold Possible Causes

• Leakage in Intake and/or Exhaust System
• Catalyst faulty
• Oxygen Sensor(s) faulty
• Oxygen Sensor(s) Control faulty

Possible Solutions

• Check Intake and Exhaust System for Leaks
• Check Catalyst
• Check Oxygen Sensor(s)
• Check Oxygen Sensor(s) Control
  • Perform Oxygen Sensor(s) Aging Check

DTC P0420: Catalyst System Efficiency Below Threashold (Bank 1)

The ECM uses sensors mounted before and after the three-way catalyst (TWC) to monitor its efficiency. The first sensor, and Air Fuel ratio (A/F) sensor, sends pre-catalyst A/F ratio information to the ECM. The second sensor, a heated oxygen sensor (O2S), sends post-catalyst information to the ECM. The ECM compares these two signals to judge the efficiency of the catalyst and the catalyst's ability to store oxygen. During normal operation, the TWC stores and releases oxygen as needed. The capacity to store oxygen results in a low variation in the post-TWC exhaust stream as shown below.
If the catalyst is functioning normally, the waveform of the heated oxygen sensor slowly switches between RICH and LEAN. If the catalyst is deteriorated, the waveform will alternate frequently between RICH and LEAN. As the catalyst efficiency degrades, its ability to store oxygen is reduced and the catalyst output becomes more variable. When running the monitor, the ECM compares sensor 1 signals (A/F sensor) over a specific amount of time to determine catalyst efficiency. The ECM begins by calculating the signal length for both sensors (for the rear oxygen sensor, the ECM uses the output voltage signal length). If the oxygen sensor output voltage signal length is greater than the threshold (threshold is calculated based on the A/F sensor signal length), the ECM concludes that the catalyst is malfunctioning. The ECM will turn on the MIL and a DTC will be set.
Hope this helps :)