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I’ve had this code pop up a couple times yet went has went away and has not returned for 800 miles. However, the exhaust does smell a bit off at points like it has a bad O2 sensor. The car also struggles a bit sometimes at 2-3k after changing gear to accelerate, but opens up at 4-5k as if everything’s normal (which based on some searching may be some sort of sensor not related to this issue?). The car drives normally under normal conditions and again is fine in higher RPMs. Just looking for clarification, if I need to replace one of the cats I will but would like some more insight. If it is the cat, would also like the part number. Thank you in advance.
Last edited by Marsalis Simms; 01-19-2022 at 12:19 PM.
Yeah I’ve seen, I’ll probably just wait a bit to see if the code pops back up; don’t know why it would go away on its own. I’ve found that the APP sensor is apparently an issue with these cars acceleration wise so will try to take care of that as well
I’ve had this code pop up a couple times yet went has went away and has not returned for 800 miles. However, the exhaust does smell a bit off at points like it has a bad O2 sensor. The car also struggles a bit sometimes at 2-3k after changing gear to accelerate, but opens up at 4-5k as if everything’s normal (which based on some searching may be some sort of sensor not related to this issue?). The car drives normally under normal conditions and again is fine in higher RPMs. Just looking for clarification, if I need to replace one of the cats I will but would like some more insight. If it is the cat, would also like the part number. Thank you in advance.
You can test your upstream O2 sensors if you want verification before replacing them, Downstream just us anti foulers.
To test upstream sensors remove sensor place in vice get multi meter set to lowest DC and get a propane torch. Heat the tip of the sensor while probing the prongs on the connector until you figure out which two will give you voltage. You then keep an eye on the output of the sensor and heat it see how high the voltage goes, looking for .9 volts or higher. If it gets cherry red hot and you don't get at least .9 replace sensor.
Now, I'm not sure if a sensor that passes this test will be as deadly accurate as a brand new one it's just a test to verify the sensor still functions adequately.
What does work remove the cat and place in bucket with purple power degreaser dont dilute or anything and let that baby sit a good 16 or so hours. Every so often move the cat up and down in the bath, if you have a torch and gloves you can heat the cat every so often to raise the temperature of the bath. After about 16 hours rinse with water BE CAREFUL DO NOT HIT THE HONEYCOMB WITH DIRECT HIGH Water PRESSURE. Just run clea ln water through the cat until the water isnt sudsy let it dry get a flashlight and see how much light makes it through. If not satisfied soak a few more hours. After about 20 hours leaving it soak longer does nothing it is what it is. I had some success with this method. Some success, not 100% success, a new cat is always a better solution.
Code has come back a couple times over the last 3k miles. Trying a cat cleaning product but at this point am willing to just order a new cat. However upon research and looking at the code it states it’s bank one which doesn’t seem to be the primary cat underneath the car but one of the smaller ones hidden behind a firewall?
Last edited by Marsalis Simms; 04-16-2022 at 09:04 AM.
if you are getting an oxygen sensor code, AND it smells bad, then I would change the oxygen sensor before I did the cats... Because it is easier and cheaper. But hey, you do what you think is best. You know what they say about free advice.. haha
if you are getting an oxygen sensor code, AND it smells bad, then I would change the oxygen sensor before I did the cats... Because it is easier and cheaper. But hey, you do what you think is best. You know what they say about free advice.. haha
i mean I’m not opposed to trying to replace that sensor. Based on my research it seemed that it was more likely to be the cat than the O2 but who knows. The code didn’t specifically state O2 sensor, just Bank 1 catalyst below threshold. Will figure out which sensor i need to buy. Situation is just strange cuz I’ve not suffered any loss in MPG or anything.
Last edited by Marsalis Simms; 04-28-2022 at 03:53 PM.
Before you replace the sensor, swap the bank 2 sensor to bank 1 and see if the code stays or moves. If it moves, then the issue is the sensor. If not then it's the cat.
we have 3 cats, 1 on each side of the engine per 3 cylinders (front near the radiator and rear near the firewall). These 2 are monitored by sensors before and after the cat. The 3rd cat that is connected to J-pipe is not monitored so it will not trigger codes.
The oxygen sensor triggering below threshold code is AFTER the cats (DOWNSTREAM). The one before the cat is the one that measures fuel trims (UPSTREAM). Swap downstream sensors and see if it moves. If it does then its the sensor. If it doesn't it's the cat.
Before you replace the sensor, swap the bank 2 sensor to bank 1 and see if the code stays or moves. If it moves, then the issue is the sensor. If not then it's the cat.
we have 3 cats, 1 on each side of the engine per 3 cylinders (front near the radiator and rear near the firewall). These 2 are monitored by sensors before and after the cat. The 3rd cat that is connected to J-pipe is not monitored so it will not trigger codes.
The oxygen sensor triggering below threshold code is AFTER the cats (DOWNSTREAM). The one before the cat is the one that measures fuel trims (UPSTREAM). Swap downstream sensors and see if it moves. If it does then its the sensor. If it doesn't it's the cat.
I'll give this a try sometime soon. I cleared the code recently after it came back and it took 1100 miles for it to return. My last TL had a similar weird smell when the O2 went bad so I'll try this in the next week or so. Haven't suffered MPG still and the car generally drives fine with the exception of the aforementioned acceleration weirdness, but I'm starting to think that may not be the cat causing it as it opens up past 3500-4k as if it's fine.
Been a while, haven’t drove the car much lately but finally started to daily it again. Got around to testing all sensors and the upstream readings are bouncing all over the place whilst the rears are just lazy. Was recommended to me to replace all sensors 🙄 will update if this fixes it.
01-19-2022, 12:16 PM
