Question about Cars & Trucks

Open Question

PO042 code Catalyst system efficiency below threshold

What do i need to replace. Cataytic convert or censor units. And were would the censor units be located?

Posted by Anonymous on

5 Suggested Answers

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

  • 87 Answers

SOURCE: I have a P0420 code catalyst efficiency below

it is a bad converter not o 2 sensor i would change the cat and both o 2 sensors

Posted on Mar 09, 2009

ghost4548
  • 776 Answers

SOURCE: 2002 Hyundai Sonata code reads P0430 what does this mean Catalyst System Efficiency Below Threshold (Bank 2)

That's a pretty RELIABLE code!... You have a bad CAT (Catalytic Converter). Trust it to be accurate. The conditions which set this code is when the Upstream O2 sensor's data/signal is compared to the Downstream sensor's data/signal... when they are nearly identical, that's when this code is set (unless you have an exhaust leak).. If there is an exhaust leak.. repair it, then retest/recheck.

Posted on May 31, 2009

  • 97 Answers

SOURCE: 420 code catalyst system efficiency below

You could have an enefficient converter. Question is what caused it to go bad? I have attended seminars on code 420, Possible causes are lack of spark or clogged fuel injectors. there have been times where the spark plug wire lays on the engine and over time it wears a weak spot in the side of the wire, its not enough to throw a miss fire code but it keeps the full amount of spark from getting to the plug and not burning the all the fuel in the cyl. A leaky injector would also cause to much fuel to be deliverd into the cyl and not get burned.

Hope this helps.

Posted on Jan 20, 2010

johnjohn2
  • 5763 Answers

SOURCE: code PO420 catalyst system efficiency below threshold

you may have a bad converter, its not cleaning the exhaust, but on the other hand a bad rear o2 sensor can also cause this problem,there is a wat to test but you would need a scan tool or scope,replace the other sensor, if light returns then replace the converter, no money lost, if you were to replace the converter the o2 sensors should also be replaced. you have 165000 miles it would be crazy not to replace sensor and install new cat, so basically your just doing it in 2 steps and may get lucky and not need a cat. good luck.

Posted on Mar 05, 2010

Testimonial: "Your information is exactly what I needed to know.I suppose I just did not want to spend the money for a cat. converter. Thanks again for your help. "

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

2 Answers

What means catalyst Efficiency below normal


      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 ...

      mechanics.stackexchange.com/.../check-engine-code-p0420-catalyst-efficie...
    Feedback

    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
    https://www.youtube.com/watch?v=-c8090n1Ihs
    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 ...

Jan 26, 2016 | Cars & Trucks

1 Answer

Code p431 and p421


P421=Warm up catalyst system efficiency below threshold, bank 1
P431=Warm up catalyst system efficiency below threshold, bank 2
Sounds like you may have clogged or damaged catalyst converters or bad 02 sensors.
Those codes I think are taking from after the catalyst by the sensors in the exhaust pipes. Be careful taking it to a mechanic for further checking since the catalyst converters are not cheap through them. If you need to replace the converters, shop around and get prices on aftermarket parts. Don't be ripped off by a hungry mechanic or especially a dealer.

Aug 17, 2013 | 2006 Mitsubishi Eclipse

1 Answer

I've had a trouble code( P0420) code come up,


Catalyst System Efficiency Below Threshold (Bank 1). OK, now tell me that again in plain English please.... let's break it down: the catalyst system being referred to is your three-way catalytic converter; so the catalytic converter is not working properly (i.e. it's not efficient). Bank 1 refers to the side of the engine which contains cylinder #1. On inline engines such as 4 & 5 cylinder engines, there is only one bank. So, to really simply things let's just say that the efficiency of the catalytic converter and/or exhaust pipe and/or O2 sensor is not so great. Hope this helps.

Mar 09, 2013 | Cars & Trucks

1 Answer

Where should i find this sensor P0342?


EXHAUST RELATED ERROR CODES

There are 711 possible PO generic DTC error codes. Only 7 of the 711 codes are exhaust related.

PO401: Insufficient EGR Flow

PO402: Exhaust Gas Recirculation (EGR) Excessive Flow Detected

PO410: Secondary Air Injection System Malfunction

PO420: Catalyst System Efficiency Below Threshold (Bank 1)

PO421: Warm-Up Catalyst Efficiency Below Threshold (Bank 1)

PO430: Catalyst System Efficiency Below Threshold (Bank 2)

PO431: Warm-Up Catalyst Efficiency Below Threshold (Bank 2)

THINGS TO ASK YOURSELF OR YOUR CUSTOMER

Have there been any driveability or performance issues with the vehicle, have there been any recent repairs or tune-up work performed, if so was the check engine light reset and were the codes recorded on previous repair orders.

Do not rely on scan tool data alone. In most applications, the customer will have the check engine light reset prior to repair. If the original cause of converter failure is intermittent, only the catalyst failure code may show up (masking the original reason for converter failure).

Nov 04, 2012 | Chevrolet Epica Cars & Trucks

1 Answer

What does a po430 code mean on a mercury cougar


EXHAUST RELATED ERROR CODES

There are 711 possible PO generic DTC error codes. Only 7 of the 711 codes are exhaust related.

PO401: Insufficient EGR Flow

PO402: Exhaust Gas Recirculation (EGR) Excessive Flow Detected

PO410: Secondary Air Injection System Malfunction

PO420: Catalyst System Efficiency Below Threshold (Bank 1)

PO421: Warm-Up Catalyst Efficiency Below Threshold (Bank 1)

PO430: Catalyst System Efficiency Below Threshold (Bank 2)

PO431: Warm-Up Catalyst Efficiency Below Threshold (Bank 2)

THINGS TO ASK YOURSELF OR YOUR CUSTOMER

Have there been any driveability or performance issues with the vehicle, have there been any recent repairs or tune-up work performed, if so was the check engine light reset and were the codes recorded on previous repair orders.

Do not rely on scan tool data alone. In most applications, the customer will have the check engine light reset prior to repair. If the original cause of converter failure is intermittent, only the catalyst failure code may show up

Nov 04, 2012 | Cars & Trucks

1 Answer

Code of PO174 1 system too lean (bank 1) Code PO420 Catalyst efficiency below threshold (bank 1) Code PO430 Catalyst efficiency below threshold (bank 2)


hi,my friend, you can try,

Check for exhaust leaks at the manifold, pipes, catalytic converter. Repair as required.

Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady).

Inspect the downstream heated oxygen sensor (HO2), replace if necessary

Replace the catalytic converter

Sep 14, 2011 | 2003 GMC Yukon XL

1 Answer

Troubleshooting code p0420


P0420 = Bank 1 catalyst system efficiency below threshold. This DTC (Diagnostic Trouble Code) is set when the O2 downstream sensor indicates/measures the amount of hydrocarbons/oxygen present in the exhaust after it passes through the converter. When this sensor detects exhaust gasses identical/near identical to the upstream O2 Sensor (the actual gasses at the exhaust port - before the converter), it will set this 'efficiency below threshold' code. The catalyst has failed to 'convert' the exhaust gasses to CO2 + Water.

Sep 11, 2011 | 2006 Hyundai Sonata

1 Answer

Code PO42O and PO43O ? Anyone know what they


The meaning of: P0420 Catalyst System Efficiency Below Threshold on Bank 1 P0430 Catalyst System Efficiency Below Threshold on Bank 2

Basically the Oxygen sensors ( one before and one after the catalytic converter ) have abnormal readings from the exhaust. Further diagnosing will need to be done by a mechanic to find the source of the problem. The possibilities could be the O2 sensors themselves, a leak in the exhaust manifold, a bad catalytic converter, and etc.

Nov 14, 2009 | 2002 Toyota RAV4

1 Answer

Error coce P0420 on OB-2 scanner


P0420 = Catalyst System Efficiency Below ThresholdCatalyst System Efficiency Below Threshold. This means that the secondary O2 sensor detects that the catalytic converter isn't working as efficiently as it should. This engine code can be triggered by any one of the following:

1.) The catalyst in the catalytic converter is cracked, clogged, or otherwise damaged.
2.) The secondary O2 sensor is malfunctioning.
3.) There is an exhaust leak.
4.) The computer unit is faulty

Sep 28, 2009 | 2006 Chevrolet Malibu

1 Answer

Catalyst System Efficiency below threshold.


Need to replace your cat converter. You can do it if you are mechanically inclined. But, most likely will need to be taken to someone with a lift. Yes it will be expensive. Look at $500-1000.

Mar 16, 2009 | 1997 Toyota Avalon

Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

30 people viewed this question

Ask a Question

Usually answered in minutes!

Top Cars & Trucks Experts

yadayada
yadayada

Level 3 Expert

75077 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22095 Answers

Randy Ohler

Level 3 Expert

14585 Answers

Are you a Car and Truck Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...