Throwing Oxygen Sensor Related Codes

I have an ses light on, and just got my computer read. It is thowing both P0420 and P0430 codes. Autozone's computer says this means bank 1 and 2 are below threshold for current engine operatings conditions??? What the hell does this mean? Does this mean both of my cats are bad or just the o2 sensors? I'm planning on purshasing lt headers and off road y in the near future, so would it be safe to ignore this until then? Also, is there any common shops that usually have the capability to delete the rear sensors, because I dont know of any around here.

in related thread i saw orion mention that gm waranty on the cats are ten yrs. . . should i try this first? even tho i "plan" on gettin the headers and off road y

It's more likely bad cats than 02's. Your choice I guess, won't cost you anything but a little down time to have the dealer replace them. Guessing you don't have to worry about emissions.

Quote:

---

Originally Posted by 2001NBMZ28

It's more likely bad cats than 02's. Your choice I guess, won't cost you anything but a little down time to have the dealer replace them. Guessing you don't have to worry about emissions.

---

ya im kinda hopin it is the cats . . . nope no emission testing here.

mine was reading the same......i changed cats,but i have other issues so i have not got to see if the lite stays off yet.....i can say i saw nothing physically wrong with the cats.....

Quote:

---

Originally Posted by astyles

mine was reading the same......i changed cats,but i have other issues so i have not got to see if the lite stays off yet.....i can say i saw nothing physically wrong with the cats.....

---

hmm. . . ill prob go ahead and try this first then.

Now . . this may not mean anything and I may sound dumb with this, but my tips get really black, fairly quickly, so in turn making me wonder if shes runnin rich. so could this be a factor in this whole situation? i know the front o2 can control air fuel ratio.

I had those two codes and new cats got rid of them. I got them under that warranty too!

Quote:

---

Originally Posted by david_viny

I had those two codes and new cats got rid of them. I got them under that warranty too!

---

good deal!!! looks like thats what i definately need to try first!

I had that problem earlier this spring. The two things I did to fix it:

1) Lucas fuel system cleaner / lubricant

2) I cleaned the Mass Airflow Sensor. Since I use a K&N, sometimes the oil ends up coating the little wires, and causes problems with the AFR. They make a cleaner designed for MAS for like $5.

Between the two, it fixed my errors.

Quote:

---

Originally Posted by Pushead

I had that problem earlier this spring. The two things I did to fix it:

1) Lucas fuel system cleaner / lubricant

2) I cleaned the Mass Airflow Sensor. Since I use a K&N, sometimes the oil ends up coating the little wires, and causes problems with the AFR. They make a cleaner designed for MAS for like $5.

Between the two, it fixed my errors.

---

really? and yours was readin these codes too? may have to do this tonight

maybe seafoam could help it too........i think my cats may have been clogged but not burned out:shrug:

Quote:

---

Originally Posted by GULLETT17

really? and yours was readin these codes too? may have to do this tonight

---

Yep same codes. I think it was still running a bit lean, but before I had a chance to hook it back up to a wideband O2, I had a valve hit a piston, and tore the engine apart. The two problems aren't related, don't worry.

so you dont have to be the original owners to get the cats swaped by the dealer guys?

Nope, as long as you have the codes show up and you're in the time/mileage bracket you should be able to get new ones. If the dealers say they have never heard of it ask them to check for it in their computer system if they didn’t already. I had to explain to them what it was and they were pretty skeptical lol, then they looked and found it. :bat:

my service engine light is on when i went to chek it it came out as both the first oxygen sensors on bank 1 and 2 are either runnig too lean or rich? is that enough evidence for them to change the cats fo me!

Quote:

---

Originally Posted by david_viny

Nope, as long as you have the codes show up and you're in the time/mileage bracket you should be able to get new ones. If the dealers say they have never heard of it ask them to check for it in their computer system if they didn’t already. I had to explain to them what it was and they were pretty skeptical lol, then they looked and found it. :bat:

---

Federal emissions warranty is 8 years or 80k miles (whichever occurs first) This covers converters and the PCM. SOME F-bodys had a special policy on the converters for 10 years or 120k miles. The only way to tell is to have the dealer diagnose the problem and figure out if it is even the converters themselves.

the dealer was goin to charge me 110 buks if it wasnt the cats that were bad just to chek them even though its a recall? i explained to the guy the codes it was throwing and i have a scanner in handy so i cheked it myself! that guy at the dealershit pissed me the fuk off!

he was like "just cause you throw those codes doesnt mean the cats are bad" was the dealer shits that strict on u guys when u got them changed?

i have the oxygen sensors, should i just instal them and then see if the codes disapear, then take it bak to the dealershit? ur help would be most appreciated thanks guys!

Quote:

---

Originally Posted by ricefordiner

i have the oxygen sensors, should i just instal them and then see if the codes disapear, then take it bak to the dealershit? ur help would be most appreciated thanks guys!

---

Put the 02 sensors in and reset the pcm and drive it. If the SES light comes on again, get the codes rescanned and then bring it back to the stealership...

Quote:

---

Originally Posted by ricefordiner

the dealer was goin to charge me 110 buks if it wasnt the cats that were bad just to chek them even though its a recall? i explained to the guy the codes it was throwing and i have a scanner in handy so i cheked it myself! that guy at the dealershit pissed me the fuk off!

---

No... there are no recalls on the converters for F-bodys. The dealership was right in having you sign for an inspection fee which would get waived if the converters were the issue. It very well could not be the converters, and you don't know unless you have your own diagnostic tools. If it turns out to be the converters than no big deal, you get them for free if you fall in the time and mileage bracket.

cool im changeing my o2s first then, im short of cash, so i hope that does the trick thanks for the tips ill be bak to uptudate on what happens!

I just got the "cat code" Po4730, which is the right cat. This is the second time, I had it replaced 2 yrs ago. By the way the warrenty on emmisions parts is 80K, and on my replacement it was 12/12. Also lets not confuse codes for cats being bad 02's because there are codes for each. The cats degrade or oxidize which the pair of 02's calculate the difference hence the code. If the computer sees a bad value to the 02 then that throws a seperate code, so replace what the computer says.
My question is would you replace the cats now if long tubes are in the future. The answer to someone elses question was that driving with that code will affect drivability, performance, and most important now is MPG.

UPDATE:
so i noticed a hissing sound the other day as i was drivin downtown (echo off the buildings allowed me to hear it well). after searchin for a while, i found that there was a leak in the hose connecting the pcv valve to the intake. i patched it temporary with duct tape. my ses light is now off. explination? would this throw this kind of code?

Quote:

---

Originally Posted by GULLETT17

UPDATE:
so i noticed a hissing sound the other day as i was drivin downtown (echo off the buildings allowed me to hear it well). after searchin for a while, i found that there was a leak in the hose connecting the pcv valve to the intake. i patched it temporary with duct tape. my ses light is now off. explination? would this throw this kind of code?

---

No. P0420 and P0430 are catalyst inefficiency codes. They can ONLY be caused by a failed converter(s). Anyone who tells you that oxygen sensors or PCM calibrations will fix the problems are completely incorrect, and obviously have no idea how the system works. There may not be a recall per se on the converters, but there is an extended warranty period for 10 years and I believe 120K miles. So if you have those codes stored, THE ONLY CAUSE IS THE CONVERTER(S). You should take the car to the dealer and have them replace converters. The diagnostic fee they are making you aware of is covering their ass in the event that a dishonest or misinformed customer comes with a check engine light and says fix it for free. It's simple, just take the car to the dealer, tell them to replace the converters under the extended emission warranty that GM issued for the converters. Tell them you owe them nothing and if they disagree, threaten to contact GM.

The PCV leak would cause a vacuum leak. The engine would run lean and may set the check engine light for a P0171 or P0174, but not catalyst inefficiency codes. It is unrelated.

Quote:

---

Originally Posted by Marc 85Z28

No. P0420 and P0430 are catalyst inefficiency codes. They can ONLY be caused by a failed converter(s). Anyone who tells you that oxygen sensors or PCM calibrations will fix the problems are completely incorrect, and obviously have no idea how the system works. There may not be a recall per se on the converters, but there is an extended warranty period for 10 years and I believe 120K miles. So if you have those codes stored, THE ONLY CAUSE IS THE CONVERTER(S). You should take the car to the dealer and have them replace converters. The diagnostic fee they are making you aware of is covering their ass in the event that a dishonest or misinformed customer comes with a check engine light and says fix it for free. It's simple, just take the car to the dealer, tell them to replace the converters under the extended emission warranty that GM issued for the converters. Tell them you owe them nothing and if they disagree, threaten to contact GM.

The PCV leak would cause a vacuum leak. The engine would run lean and may set the check engine light for a P0171 or P0174, but not catalyst inefficiency codes. It is unrelated.

---

hhmmmm. . . see this is what i thought. . . and thats what i planned on doing is goin to the dealer the get the cats replaced under the extended warranty. buuut. . . it aint gonna matter now if they ses light is now off tho right? i guess if the cats are bad, the ses light will come back on and its just a coincidence it went off in the first place :dunno:

Quote:

---

Originally Posted by Marc 85Z28

No. P0420 and P0430 are catalyst inefficiency codes. They can ONLY be caused by a failed converter(s). Anyone who tells you that oxygen sensors or PCM calibrations will fix the problems are completely incorrect, and obviously have no idea how the system works. There may not be a recall per se on the converters, but there is an extended warranty period for 10 years and I believe 120K miles. So if you have those codes stored, THE ONLY CAUSE IS THE CONVERTER(S). You should take the car to the dealer and have them replace converters. The diagnostic fee they are making you aware of is covering their ass in the event that a dishonest or misinformed customer comes with a check engine light and says fix it for free. It's simple, just take the car to the dealer, tell them to replace the converters under the extended emission warranty that GM issued for the converters. Tell them you owe them nothing and if they disagree, threaten to contact GM.

The PCV leak would cause a vacuum leak. The engine would run lean and may set the check engine light for a P0171 or P0174, but not catalyst inefficiency codes. It is unrelated.

---

Not all the LS1 years have the extended warranty, and it only falls in certain VIN breaks too. And regardless if you KNOW it is the converters or not, policy and procedure is to have the customer sign for the diagnostic fee. If it is the converters, it will be waived. Threatening to call GM will do nothing to the extent of a dealer inspecting the car for free. You can't just tell a dealer to replace something that is not broken.

Quote:

---

Originally Posted by konigandy6

Not all the LS1 years have the extended warranty, and it only falls in certain VIN breaks too. And regardless if you KNOW it is the converters or not, policy and procedure is to have the customer sign for the diagnostic fee. If it is the converters, it will be waived. Threatening to call GM will do nothing to the extent of a dealer inspecting the car for free. You can't just tell a dealer to replace something that is not broken.

---

All 2000-2002 V8 Camaro and Firebird are covered. I know the procedures, I'm in the industry. Threatening a service manager with going over his head when done right will get you anything, and I do mean anything, that you want.

GULLETT17 - It does not matter if the SES light is on or not. What matters is if the DTCs (codes) are stored in the PCM. As long as you do not clear them or remove power from the PCM they can stay in memory even if the light is off. And in some cases, GM PCMs are capable of displaying cleared DTCs (kind of like a Windows recycle bin) - so a good technician could pick up on that. The reason the light went off is because the PCM has not seen the converters being inefficient in numerous drive cycles. The DTCs are probably still there. It would be a good idea to verify that with AutoZone just prior to the dealer visit though.

Quote:

---

Originally Posted by Marc 85Z28

All 2000-2002 V8 Camaro and Firebird are covered. I know the procedures, I'm in the industry. Threatening a service manager with going over his head when done right will get you anything, and I do mean anything, that you want.

GULLETT17 - It does not matter if the SES light is on or not. What matters is if the DTCs (codes) are stored in the PCM. As long as you do not clear them or remove power from the PCM they can stay in memory even if the light is off. And in some cases, GM PCMs are capable of displaying cleared DTCs (kind of like a Windows recycle bin) - so a good technician could pick up on that. The reason the light went off is because the PCM has not seen the converters being inefficient in numerous drive cycles. The DTCs are probably still there. It would be a good idea to verify that with AutoZone just prior to the dealer visit though.

---

I am in the industry as well, and know for a fact that it will not get you anything you want. But, all dealerships are different, and my dealer, when the customer calls GM, GM calls my service manager, he then says yes or no. Some dealers do not have the luxury of the manager having the goodwill/customer satisfaction warranty power, mine does. And from personal experience, they will not just replace parts if they are not broken.

I have a question concerning this matter. What does it mean then when your computer is throwing codes that say o2 sensors reporting low voltage on a given bank? Would this mean the o2 sensors are bad or possably a bad cat?

Quote:

---

Originally Posted by Marc 85Z28

All 2000-2002 V8 Camaro and Firebird are covered. I know the procedures, I'm in the industry. Threatening a service manager with going over his head when done right will get you anything, and I do mean anything, that you want.

GULLETT17 - It does not matter if the SES light is on or not. What matters is if the DTCs (codes) are stored in the PCM. As long as you do not clear them or remove power from the PCM they can stay in memory even if the light is off. And in some cases, GM PCMs are capable of displaying cleared DTCs (kind of like a Windows recycle bin) - so a good technician could pick up on that. The reason the light went off is because the PCM has not seen the converters being inefficient in numerous drive cycles. The DTCs are probably still there. It would be a good idea to verify that with AutoZone just prior to the dealer visit though.

---

thanks man! i guess i didnt know the codes were stored even if after the light goes off. . . but would autozone be able to read them if the ses light is on? some readers can only "see" codes if the ses light is on, right?

Quote:

---

Originally Posted by GULLETT17

thanks man! i guess i didnt know the codes were stored even if after the light goes off. . . but would autozone be able to read them if the ses light is on? some readers can only "see" codes if the ses light is on, right?

---

Any good OBDII scanner should be able to pick up current codes and history codes. Nothing beats the good ole TechII though, and I have never used the autozone scanner myself so I am not sure if it can cycle through history.

Quote:

---

Originally Posted by hamptonwsk

I have a question concerning this matter. What does it mean then when your computer is throwing codes that say o2 sensors reporting low voltage on a given bank? Would this mean the o2 sensors are bad or possably a bad cat?

---

Those would be bad o2 sensors.

Quote:

---

Originally Posted by konigandy6

Any good OBDII scanner should be able to pick up current codes and history codes. Nothing beats the good ole TechII though, and I have never used the autozone scanner myself so I am not sure if it can cycle through history.

---

good to know . . . thanks man!

Here is the special policy on the converters (NOT A RECALL)

#05513: Special Coverage Adjustment - Catalytic Converter Extended Warranty - (Nov 27, 2006)


Subject: 05513 - SPECIAL COVERAGE ADJUSTMENT - CATALYTIC CONVERTER EXTENDED WARRANTY


Models: 2000-02 CHEVROLET CAMARO

2000-02 PONTIAC FIREBIRD

EQUIPPED WITH 5.7L V8 (RPO LSI - VIN G) ENGINE




--------------------------------------------------------------------------------

Condition
Some customers of 2000-02 Chevrolet Camaro and 2000-02 Pontiac Firebird model vehicles, equipped with a 5.7L V8 (RPO LS1 - VIN G) engine, may experience a failure of the left or right catalytic converter.

Special Coverage Adjustment
This special coverage covers the condition described above for a period of 10 years or 120,000 miles (193,000 km), whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership. The repairs will be made at no charge to the customer.

For vehicles covered by Vehicle Service Contracts, all eligible claims with repair orders on or after November 27, 2006 are covered by this special coverage and must be submitted using the labor operation codes provided with this bulletin. Claims with repair orders prior to November 27, 2006 must be submitted to the Service Contract provider.

Vehicles Involved
Involved are all 2000-02 Chevrolet Camaro and 2000-02 Pontiac Firebird model vehicles, equipped with a 5.7L V8 (RPO LS1 - VIN G) engine and built within the following VIN breakpoints:

Year
Division
Model
From
Through

2000
Chevrolet
Camaro
Y2100004
Y2177266

2000
Pontiac
Firebird
Y2100002
Y2177254

2001
Chevrolet
Camaro
12100001
12150441

2001
Pontiac
Firebird
12100004
12150442

2002
Chevrolet
Camaro
22100001
22172467

2002
Pontiac
Firebird
22100003
22172466


Parts Information
Parts required to complete this special coverage are to be obtained from General Motors Service and Parts Operations (GMSPO).

Part Number
Description
Quantity/Vehicle

12609727
Asm, Catalytic Converter and Pipe LH
1

12609726
Asm, Catalytic Converter and Pipe RH
1

12555806
Gasket, Exh Manif Pipe LH
1

88891747
Gasket, Exh Manif Pipe RH
1


Customer Notification
General Motors will notify customers of this special coverage on their vehicles (see copy of typical customer letter included with this bulletin - actual divisional letter may vary slightly).

Service Procedure
Refer to Oxidation Catalytic Converter Replacement (5.7L Left and Right) in SI for removal and installation instructions.

Claim Information
For vehicles repaired under the terms of this special coverage submit a claim with the information indicated below:

Repair Performed
Part Count
Part Number
Parts Allow
CC-FC
Labor Op
Labor Hours
Net Item

Inspect and Replace Catalytic Converters
--
--
*
MK-95
T5656
0.9
N/A

Customer Reimbursement (Canadian & Export Dealers/US CAC)
N/A
N/A
N/A
MK-95
T5657
0.2
**

* The "Parts Allowance" should be the sum total of the current GMSPO Dealer net price plus applicable Mark-Up or Landed Cost Mark-Up (for Export) for catalytic converter parts needed to complete the repair.

** The amount identified in the "Net Item" column should represent the customer reimbursement amount.


Customer Reimbursement - For US
All customer requests for reimbursement of previously paid repairs for the special coverage condition will be handled by the Customer Assistance Center, not by dealers.

A General Motors Customer Reimbursement Procedure and Claim Form is included with the customer letter.

Important: Refer to the GM Service Policies and Procedures Manual, section 6.1.12, for specific procedures regarding customer reimbursement and the form.

Customer Reimbursement - For Canada and Export
Customer requests for reimbursement of previously paid repairs for the special coverage condition are to be submitted to the dealer prior to or by November 30, 2007. Repairs must have occurred within the 10 years of the date the vehicle was originally placed in service, or 193,000 km (120,000 miles), whichever occurs first.

When a customer requests reimbursement, they must provide the following:

• Proof of ownership at time of repair.


• Original paid receipt confirming the amount of unreimbursed repair expense(s) (including Service Contract deductibles), a description of the repair, and the person or entity performing the repair.


If the work was done by someone other than a GM dealership, the amount of reimbursement will be limited to the amount that the repair would have cost GM to have it completed by a GM dealership.

December 2006
Dear General Motors Customer:

As the owner of a 2000-02 Chevrolet Camaro or 2000-02 Pontiac Firebird model vehicle, equipped with a 5.7L V8 engine, your satisfaction with our product is very important to us.

This letter is intended to make you aware that some 2000-02 Chevrolet Camaro and 2000-02 Pontiac Firebird model vehicles, equipped with a 5.7L V8 engine, may have a failure of the left or right catalytic converter.

This is not a recall. Do not take your vehicle to your General Motors dealer as a result of this letter unless you believe that your vehicle has the condition as described above.

What We Have Done: General Motors is providing owners with additional protection for the right and left catalytic converters. If this condition occurs on your 2000-02 Chevrolet Camaro or 2000-02 Pontiac Firebird within 10 years of the date your vehicle was originally placed in service, or 120,000 miles (193,000 km), whichever occurs first, the condition will be repaired for you at no charge .

What You Should Do: Repairs and adjustments qualifying under this special coverage must be performed by a General Motors dealer. You may want to call the service department at your dealer to find out how long they will need to have your vehicle so that you may schedule the appointment at a time that is convenient for you. This will also allow your dealer to order parts if they are not already in stock. Keep this letter with your other important glove box literature for future reference.

Reimbursement: The enclosed form explains what reimbursement is available and how to request reimbursement if you have paid for repairs for the special coverage condition.

If you have any questions or need any assistance, just contact your dealer or the appropriate Customer Assistance Center at the number listed below. The Customer Assistance Center’s hours of operation are from 8:00 AM to 11:00 PM, EST, Monday through Friday.

Division
Number
Text Telephones (TTY)

Chevrolet
1-800-630-2438
1-800-833-2438

Pontiac
1-800-620-7668
1-800-833-7668

Guam
1-671-648-8650


Puerto Rico - English
1-800-496-9992


Puerto Rico - Español
1-800-496-9993


Virgin Islands
1-800-496-9994



We are sorry for any inconvenience you may experience; however we have taken this action in the interest of your continued satisfaction with our products.

General Motors Corporation

Enclosure

05513

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

wow thanks man!!!

the autozone computers are junk i was throwin o2 codes so i replaced both sensors, still not fixed. got the cats looked those were fine....the problem, low fuel pressure, wtf is that all about? i got the new fuel pump put it and now everything is sound so i dunno.

Quote:

---

Originally Posted by 1998 T/A

the autozone computers are junk i was throwin o2 codes so i replaced both sensors, still not fixed. got the cats looked those were fine....the problem, low fuel pressure, wtf is that all about? i got the new fuel pump put it and now everything is sound so i dunno.

---

well thats something to keep in mind . . . the ses light still has not came on since i fixed the pcv hose

Quote:

---

Originally Posted by 1998 T/A

the autozone computers are junk i was throwin o2 codes so i replaced both sensors, still not fixed. got the cats looked those were fine....the problem, low fuel pressure, wtf is that all about? i got the new fuel pump put it and now everything is sound so i dunno.

---

Just because you have a code for a component does not mean that component has failed. The code gives you information on what system has failed. Diagnosis is still required. That and the idiots at AutoZone do not have ANY diagnostic capabilities. What codes were stored? Many times they identify codes incorrectly.

Quote:

---

Originally Posted by Marc 85Z28

Just because you have a code for a component does not mean that component has failed. The code gives you information on what system has failed. Diagnosis is still required. That and the idiots at AutoZone do not have ANY diagnostic capabilities. What codes were stored? Many times they identify codes incorrectly.

---

Exactly!

autozone isnt a repair shop in the first place dudes just cause they cant figure out what your problem doesnt necessarily make em idiots they arnt mechanics.

Quote:

---

Originally Posted by ricefordiner

autozone isnt a repair shop in the first place dudes just cause they cant figure out what your problem doesnt necessarily make em idiots they arnt mechanics.

---

Well if you look at it like that, does it give them the right to then try to sell you parts that possibly won't fix the problem?

if the car was scanned and the code came up as o2s then it had to be the sensors rite and maybe the it was the fuel pressure too! cause on my car i had an o2 code pending code got the sensors the light didnt come off but the peding code did erase!

i agree that they shouldnt sell parts jus to sell thats fukd up of them if that was their intension!