Question about 1998 GMC Sierra

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P 0430 & p0420 catalyst system

98 4wd gives these codes. the converters are punched out. are there any disadvantages to this? A scan tool test caused these trouble codes I think, the bank 2 sensors output should change slower than bank one sensors if im reading correctly. Does this affect any other systems operation. I'm also getting a constant p0440 and haven't tracked that down yet

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Code P0440 EVAP system malfunction conditions.possibles causes fuel filler cap loose damaged or missing.fuel tank pressure sensor damaged or failed.fuel tank vapor lines clogged disconnected purge valve vapor line clogged damaged disconnected.purge or vent solenoid power circuit is open check fuse the charcoal canister could be loaded with fuel. you have to replace catalyst converters cant gut them out if both failed you have engine mechanical problem causing rich fuel mixture loading up gas in both converters causing them to burn out.make sure engine well tune check for intake leaks weak ignition spark.

Posted on Nov 18, 2013

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Here are some solutions to your codes and possible causes, maybe you have seen these pages already. when you say the converters are punched out, does that mean there are holes in them? a scan tool does not cause trouble codes, it detects them.

http://www.obd-codes.com/p0440
http://www.obd-codes.com/p0420
http://www.obd-codes.com/p0430

Posted on Nov 18, 2013

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Posted on Jan 02, 2017

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SOURCE: code P0420 keeps reoccuring - catalyst below threshold bank 1

NEW GAS CAP same thing on 99 Tahoe GAS CAP

Posted on Mar 22, 2009

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SOURCE: 3 codes present on my 2002 Envoy. p0172, p0420, and p0340,

Track the p0340 first camshaft timing is very important and could possibly cayse your other codes,Call your local GMC dealer I think I remember a bulletin about this code.

Posted on Aug 23, 2009

  • 630 Answers

SOURCE: i have a 2001 yukon

po 0102 is mas air flow sensor maf/vaf
p0171 bank 1 too lean
p0174b bank 2 too lean
What you have here is either a defective mass air flow sensor and or a possible broken loose or rotted vacuumn line or hose creating this havov, with the engine warm and idling in Park tap the air flow sensor in its housing and see if the engine gets upset(rough) if so replace the sensor its expensive.
If ok have the vac system checked for possible leaks in the hoses at around the intake manifold gasket area etc, fix and replace as needed.

Posted on Nov 05, 2010

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Error codes


Christopher, BMW P0430 code catalyst efficiency fault, the converter is no longer able to do its job and may need replace.
Check the attached links very informative, instruction and guides, Good luck
"I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info."
JE Robison Service Bosch Car Service Specialists the blog Those dreaded...
P0430 Replace the O2 sensor
P0430 P0420 Catalyst inefficiency do have to replace cats E46Fanatics
P0430 OBD II Trouble Code

Jun 03, 2016 | 2004 BMW X3 2.5i

Tip

I get OBD codes P0420 and P0430



P0420 and P0430

P0420 means Catalyst System Efficiency Below Threshold, Bank 1

P0430 means Catalyst System Efficiency Below Threshold, Bank 2

It means that the O2 sensors are good, and the O2 sensors are telling you that your catalytic converter, in the exhaust system is not working fine, as its emissions are polluting the air too much.

The catalytic converter is part of the exhaust system. The way to test this part is by doing an emission test. The two OBD codes that you are getting are already a test telling you that the converter must be replaced, unless an emission test done at a garage says the opposite.

This kind of problem will trigger the check engine light, and your car will also waste too much fuel.
You also risk to get in trouble if the car goes through an Air Pollution control, as the car won't pass an emission test in this condition.

To conclude, the Catalyst System must be replaced, the O2 Sensors are fine.

This is a repair that should be done at a garage, however you can find DIY instructions here:How to Replace a Catalytic Converter or you can get more detailed instructions, and step by step illustrated procedure purchasing a repair manual.

on May 27, 2009 | 2003 Chrysler 300M

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

Can catalytic converter cause a PO65O code


Pesky PO420 Codes - Eastern Catalytic

www.easterncatalytic.com/education/tech-tips/pesky-p0420-codes/
One of the most annoying is the persistent PO420 diagnostic code (Catalyst System ... not only shows its teeth when the catalytic converter is on the blink, but can also be ... Most, if not all, catalytic converter failures are caused by a problem or ...

P0420 Error Code: Catalyst System Efficiency Below ...

www.obd-codes.com/p0420
Repair information for the OBD-II trouble code P0420 - Catalyst System Efficiency ... If they have failed, it is likely due to something else that caused it to fail. ... the catalytic converter is broken or failed, it may be restricting the exhaust which will ...

explaining trouble codes po420 - po421 - Discount Catalytic ...


Jan 16, 2016 | Cars & Trucks

2 Answers

P0420 fault not going away


covers other aspects as well.

P0420 Chevrolet - Catalyst System Low Efficiency Bank 1 Repair Importance Level: 2/3 Repair Difficulty Level: 2/3 alt="What does this mean?"> alt="PDF"> alt="Share Code"> 3 alt="P0420 Chevrolet Comments"> ' Add Comment alt="Close Selection"> http://engine-codes.com/p0420_chevrolet.html Forum Code Possible causes - Three way catalyst converter Bank 1
- Exhaust tube
- Intake air leaks
- Fuel injectors may be faulty
- Fuel injector leaks
- Spark plugs may be faulty
- Improper ignition timing
- Powertrain Control Module (PCM)
alt="What does this mean?"> What does this mean? Tech notes As the code description implies the P0420 code means that the vehicle's control module has detected that the three-way catalytic converter is not working properly (is not as efficient as the factory is expecting). Replacing the oxygen (O2) sensors may sometimes fix the code, but in most cases the catalytic convert needs to be replaced to fix the problem. If the P0420 code is combined with other codes, try fixing the other codes first.
alt="What does this mean?"> What does this mean? When is the code detected? If a condition exists which causes the Powertrain Control Module (PCM) to detect excessive Bank 1 HO2S #2 activity outside of an acceptable range for an extended period of time, the PCM will set the P0420 code. This indicates that the three-way catalytic converters oxygen storage capacity is below a threshold considered acceptable. Possible symptoms - Engine Light ON (or Service Engine Soon Warning Light) P0420 Chevrolet Description In order to maintain a reasonably low emissions of Hydrocarbons (HC), Carbon Monoxide (CO), and Oxides of Nitrogen (NOx), the engine controls system uses a three-way catalytic converter. The catalyst within the converter promotes a chemical reaction which oxidizes the HC and CO present in the exhaust gas. This reaction converts them into harmless water vapor and Carbon Dioxide. The catalyst also reduces NOx, converting it to Nitrogen. The Powertrain Control Module (PCM) monitors this process using Bank 1 HO2S #2. Bank 1 HO2S #2, located in the exhaust stream past the three-way catalytic converter, produces an output signal which indicates the oxygen storage capacity of the catalyst. This determines the catalysts ability to convert exhaust emissions effectively. If the catalyst is functioning correctly, the Bank 1 HO2S #2 signal will be far less active than that produced by Bank 1 HO2S #1.


Read more: http://engine-codes.com/p0420_chevrolet.html#ixzz3n9JdbrFG

Sep 29, 2015 | 2009 Chevrolet Lumina SS

3 Answers

How do I fix this code p0420


You need to have it check out by a qualified repair shop because you don't want to guess on this one ! This has to do with the catalytic converter , if it's work or not ! The car needs to be hook up a up scale scan tool to check it out . Catalytic converters can cost as much as a Thousand dollars , so you want to be sure ! How To Diagnose Check Engine Light Code P0420 Catalyst Bank 1

Mar 14, 2015 | 2001 Dodge Grand Caravan

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

2 Answers

Trouble code po420 2007 solstice


P0420 - Catalyst System Efficiency Below Threshold Bank 1xicon.jpghttp://engine-codes.com/p0420.htmlForum CodePossible causes- Three way catalyst converter Bank 1
- Exhaust tube
- Intake air leaks
- Fuel injectors may be faulty
- Fuel injector leaks
- Spark plugs may be faulty
- Improper ignition timing
- Engine Control Module (ECM) Tech notes The most common cause it the three way catalyst converter Bank 1. Changing just the O2 sensor usually don't repair the problem. If the P0420 code is combined with other codes, try fixing the other codes first.

Jul 06, 2012 | 2007 Pontiac Solstice Convertible

3 Answers

Code p0420


Repair information for the OBD-II trouble code P0420 - Catalyst System Efficiency Below Threshold (Bank 1) Probably needs a catalytic converter

Apr 06, 2010 | 1999 Ford Contour

2 Answers

Where is the catalyst converter located


In the exhaust line...
768c28a.jpg

DTC P0420: 1/1 CATALYTIC CONVERTER EFFICIENCY
NOTE:For component location, see COMPONENT LOCATIONS . For connector identification, see CONNECTOR IDENTIFICATION . For circuit identification and wiring diagram, see WIRING DIAGRAMS article. After each repair procedure has been completed, reconnect all components. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS to ensure system is functioning properly.

Monitored & Set Conditions
Catalytic converter efficiency is monitored after engine warms up to 158°F (70°C), throttle has been open for 180 seconds at vehicle speed more than 18 MPH, with engine speed at 1200-1700 RPM and MAP vacuum 15-21 in. Hg. DTC will set in Powertrain Control Module (PCM) memory when PCM senses catalyst efficiency deteriorated to a predetermined value. Possible causes for DTC to set are: intermittent condition, exhaust leak, engine mechanical problem, defective catalytic converter or upstream Heated Oxygen Sensor (HO2S) is older than downstream HO2S.
Testing
NOTE:1/1 HO2S may also be referred to as an upstream oxygen sensor. On 2.4L, 1/1 HO2S is located on exhaust manifold flange. On 3.3L and 3.8L, 1/1 HO2S is located on right exhaust manifold flange (manifold closest to firewall).

NOTE:If any O2 sensor DTCs are set along with P0420, diagnose those DTCs before continuing with this test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS .

Turn ignition on. Using scan tool, read DTCs. If Good Trip counter is displayed for DTC P0420 and displayed count is "0", go to next step. If Good Trip counter is not displayed for DTC P0420 or displayed count is not "0", go to step 7 .
Inspect catalytic converter for damage, discoloration caused by overheating and for converter coming apart internally. Replace catalytic converter as necessary. If catalytic converter is okay, go to next step.
Start engine and allow it to idle. Check for exhaust leaks between engine and 1/1 HO2S. Repair exhaust system as necessary. If exhaust system is okay, go to next step.
Check exhaust for excessive smoke caused by coolant entering combustion chambers or high oil consumption. If excessive smoke caused by coolant entering combustion chambers or high oil consumption does not exist, go to next step. If excessive smoke caused by coolant entering combustion chambers or high oil consumption exists, repair engine as necessary and replace catalytic converter.
NOTE:A new downstream HO2S used along with an aging upstream HO2S may cause DTC P0420 to set.

If downstream HO2S has been replaced without replacing upstream HO2S, replace upstream HO2S. If downstream HO2S has not been replaced recently or downstream HO2S has been replaced along with upstream HO2S, go to next step.
At this time, catalytic converter is assumed to be defective. Replace catalytic converter.
NOTE:A new downstream HO2S used along with an aging upstream HO2S may cause DTC P0420 to set. Review vehicle repair history and repair as necessary.

Conditions for DTC to set do not exist or fault is an intermittent problem. Start engine and allow it to idle. Ensure engine is at normal operating temperature. Using scan tool, monitor parameters related to DTC while wiggling connectors and wiring harness. If value changes while wiggling connectors and wiring harness, repair connectors and wiring harness where wiggling caused value to change. If value does not change, review Freeze Frame data using scan tool. Attempt to duplicate condition that caused DTC to set. Check for any related technical service bulletins that may apply. Visually inspect related connectors and wiring harness. Repair connectors and wiring harness as necessary. If no problems are indicated, test is complete.

Good luck.

Oct 14, 2009 | 2000 Chrysler Town & Country

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