Hello, I have a 2009 Tahoe 2wd 189,000 5.3 and I brought it to my mechanic because it has had a cel light on. The light has been on for a couple of weeks but no problems with the Tahoe runs smooth, smooth idle everything. He says Cyl 4 says a misfire so he ran it for a little no misfire nothing wrong. Also, he says there are 4 codes about the O2 sensors he says. He doesn't do exhaust but I asked the shop up the street he says it sounds like the cats are going bad. The shop up the road is a fee to diagnose so I haven't brought it up there yet. Does this sound like the cats or a sensor problem? Just tryna see where to start.
O2 Sensors Help
- Thread starter Timee
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Need to know the codes that were pulled?
donjetman
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and fuel trim #s
The mechanic said 4 o2 senor codes but when I went to autozone code P0430 was the only code there
and how do I get my fuel trim #?
donjetman
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With a scan tool and the engine running, check u tube
I dont have a reader going to have to bring it to someone.
Last edited:
swathdiver
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Your mechanic's speak in fluff, no specifics. Might be because you are not yet learned about cars.
Go on Amazon and get an OBDII adapter that will work with your phone and download Torque Pro or something similar.
Now YOU can pull up the codes yourself and not rely on someone else.
The only time a cat converter code is a false positive is with a massive exhaust leak in front of it. A cat code does not mean it's time for new sensors. Having said that, at 189K miles, yours are 89K miles overdue for replacement. $180 or so delivered for all 4 plus labor or tools if you DIY.
Cheap Chinese Communist catalytic converters do not last. I replaced mine with a Magnaflow Y-Pipe and Cats almost six years ago and still going strong.
It would be way easier to follow what you are trying to convey if you stopped making just one long sentence. Punctuation helps me understand, at least.
That P0430 code is point to one bank and not all 4 sensors. If there were 4 codes and he cleared them, the P0430 would have cleared too but that one code could have come back when you drove to AZ. IMO, if you need any sensors at all, I would do all 4 at the same time with quality AC Delco or Genuine GM sensors or Delphi. Others will have a different take on this.
Say I go and get all new sensors and the code is still there would hollowing out the cats or removing them completely get rid of the cel light? Just wondering because i’ve seen the price of new cats and trying to not spend a lot, as I have a new vehicle. I live in a no emmisons testing state also.
You can do what you want but replacing all 4 sensors may not fix. that is just throwing parts at it. If you want to be sure, it needs to be diagnosed. I would drive around for a bit and see if only the P0430 code stays and nothing else pops up. then you can tackle the one code/ I did not look and am not gonna scroll back. Does it drive fine? Just the CEL only?
swathdiver
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Hollowing out the cats will guarantee that the light stays on! There is a modification you can do to trick the sensors into believing the cats are working though. Search the forum for that.
Marky Dissod
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No, this would create a different Check Engine light for catalytic converter failure.
IFF you live in a state where you can pass 'emissions' inspections with a Check Engine light on - in NYC, no Check Engine light and all monitors ready = PASS with flying colors - then hollow out the cats and live with a permanent Check Engine light that won't let you know if anything else goes wrong.
Read OR VietVet's signature, then think about this:
Another vehicle is likely more expensive than properly maintaining this one.
Drives really good I feel no power loss or anything. And it’s just the cel.
even if the 02 sensors were replaced on time with a previous owner it is close to time to do them again anyway, gm rates them for 100k miles, if they were never changed then ya they are way overdue.
you can change them yourself without too much trouble they can be difficult to sometimes get loose and can be difficult to reach with a tool, so you may need to try different combinations of adapters and you will want a 02 sensor socket, the socket has a notch in it to allow for the wire connector to not get destroyed.
you need 2 of each front and rear, 4 total which side they go on doesn't matter, the front and rear connectors are different so not hard to figure out.
if they come out easy you can change them all in 30 minutes
if my mechanic told me it needs o2 sensors but he doesn't do exhaust work. that would make me question everything.
exhaust work is cutting, welding repairing exhaust. sensors just screw into the exhaust pipe, I've never heard a mechanic say they wouldn't do o2 sensors. they usually throw those at everything. since technically they are a wear item.
I'd basically do a tune up if you haven't in a while, new plugs wires and o2 sensors. if you have issues from there you have a good base. that's not really throwing parts at it in my book since most people haven't changed any of that before and it's time anyways.
if you have access to an android phone. I believe torque app isn't iPhone, but they have others I'd guess, but this is a good cheap obd2 reader and 5$ torque app you'll be able to do some useful troubleshooting.
for Android Phones ONLY - Wireless Bluetooth Diagnostic OBD2 Scanner Car Code Reader and Scan Tool for All 1996 & Newer Vehicles ELM327 Compatible OBDII https://a.co/d/9e6Qjy5
exhaust work is cutting, welding repairing exhaust. sensors just screw into the exhaust pipe, I've never heard a mechanic say they wouldn't do o2 sensors. they usually throw those at everything. since technically they are a wear item.
I'd basically do a tune up if you haven't in a while, new plugs wires and o2 sensors. if you have issues from there you have a good base. that's not really throwing parts at it in my book since most people haven't changed any of that before and it's time anyways.
if you have access to an android phone. I believe torque app isn't iPhone, but they have others I'd guess, but this is a good cheap obd2 reader and 5$ torque app you'll be able to do some useful troubleshooting.
for Android Phones ONLY - Wireless Bluetooth Diagnostic OBD2 Scanner Car Code Reader and Scan Tool for All 1996 & Newer Vehicles ELM327 Compatible OBDII https://a.co/d/9e6Qjy5
Chris Mosher
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Sounds like she needs a good 100mph clean out for a few miles. If the cat was bad I would think you’d notice a performance issue and/or smell.
GRAYGEORGE
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Pickup a pack of the old style spark plug non-fouler, drill it out so the sensor will fit in it, then put it in service to see if code comes back. https://www.autozone.com/ignition-t...ce/spark-plug-non-fouler?filterByKeyWord=spar
Lol. The ol' Italian Tuneup!
