I have a 2010 Chevy Traverse with approx. 150000 miles on it. About a month and a half ago I replaced the bank 1 converter and the O2 sensors. I got a PO420 code. Cleared the code and the light has not come back on. Trying to figure out why I get the code and what I need to look before I go and spend several hundreds or thousands of dollars again for repairs.
Thank you for your quick reply. How do I check fuel trim levels? What do you mean plus/minus 10? Oil consumption is about 1/2 quart every month. I was told by a mechanic at Chevy this is normal considering the mileage.
And if the fuel trims are off how do they get adjusted so that they are correct? Thank you Eric
Monitor engine parameters with scan tool. Fuel trims being one of the parameters. If trims are too far off it will set an error code. Error code is used to help pin point problem. Probable that cat converter on the other bank is close to setting an error code. Simply due to age/millage. Be aware of a flashing the check engine light. Indicates strong misfires that can damage converters. Fix this right away if you come across it in the future.
All three cats were changed over the past year.
Ok, so looks like that 9-10 years is the life for your cat system. How many miles?
150000. So how do you adjust the fuel trims?
Fuel trims are adjusted by PCM with sensors input/feedback. ECT/IAT/MAF/A/F sensor. When sensors indicate abnormal data then diagnose to find problem. Bringing data back to normal adjusts the fuel trim. Discover more fuel Honda Fit OBD If you have scanner to read fuel trims you can set a baseline reading for trim/sensors when engine running good.
Thank you for that info. I cleared the light the other day and after 103 miles of driving it came back on with same code. The car ran very good no decrease in mileage. I noticed that there is a small puddle of oil in the mass air flow corrugated hose. Would that cause the check engine light to come on with that code?
"About a month and a half ago I replaced the bank 1 converter and the O2 sensors. I got a PO420 code. Cleared the code and the light has not come back on." "'I cleared the light the other day and after 103 miles of driving it came back on with same code." Alright think i got it now. So after changing the bank one cat and O2 sensors month and half ago the P0420 still comes on intermittently correct? Was the diagnoses/repair done by a qualified shop? If so they owe you a redo for a misdiagnoses/repair. "I noticed that there is a small puddle of oil in the mass air flow corrugated hose. Would that cause the check engine light to come on with that code?" Wouldn't think so but a scan of the engine parameters would help determine what if any effect it has.
Yes it was done by a Chevy dealer in my neighborhood. I just ended up in a big argument with them after spending $2100 for the first repair and another $1600 for the second repair now I have the code coming up again. They told me they would have to connect the car to the computer and do a diagnoses and want to charge me another $150 to tell me what is wrong with it. Because there appears to be something else wrong with the car. I do not want to deal with the dealership again. However the next Chevy dealer is about 100 miles away. I have a family friend that is a mechanic however he lives in Massachusetts and I am in upstate New York. It might be worth it for me to take the drive. I know he will only charge me for parts. Ok back on Feb 10th I was getting codes PO134, PO300, PO301, PO303, PO305 and the car would not run. They changed the rear cat (the last one) and O2 sensor. 3 days later I was getting a code of PO420 the told me that the bank 1 cat was bad because of the misfires. So they replace the bank one cat and O2 sensor. Now you see why I got into an argument with them. Like I said earlier I had the hose off from the airbox to the throttle body and when I went to put it back on I see a light brown murky liquid inside of it. If I had your mail address I could send you a pic. I am at a loss now. Thank you
Are there (2) O2 sensors on bank 1?
Your in luck. Call Eric O owner of South Main Auto. He will be able to sort this out for you. South Main Auto Repair LLC 47 S Main St, Avoca, NY 14809 Phone: (607) 566-2225 Personally with the money that was spent without a fix i'd file a small claim against the dealer.
Oh I plan on it believe me. It is a shame. Avoca is about 5 hours from me.
"Ok back on Feb 10th I was getting codes PO134, PO300, PO301, PO303, PO305 and the car would not run. They changed the rear cat (the last one) and O2 sensor." P0134- changing bank 1 sensor 1 probably fixed the PO134, PO300, PO301, PO303, PO305. Changing the rear cat in this case doesn't compute. Reason being rear cat is downstream of both banks and would have effect on both banks. The owe you money back on the cat install. "3 days later I was getting a code of PO420 they told me that the bank 1 cat was bad because of the misfires. So they replace the bank one cat and O2 sensor." Question - after this replacement the P0420 continued to set intermittently correct? If so they own you money back for misdiagnoses/faulty repair.
I would think they owe me money back but good luck trying to get it. I will have to take them to small claims court. When they change the last cat (rear) I drove about three days and got the PO420 code. They told me bring the car back in 6 hours later they told me that the bank 1 cat the front one that you can see when you open the hood was bad and needed to be replaced along with the O2 sensor. Two days later and $1600 the car was running fine no codes. I did a trip to Maine from NY another to Boston from NY a trip to Maryland and 3 trips to PA. the other day I was driving home from work and the check engine light came on I put my scanner on it (not an expensive one) and I got the code of PO420. Called the dealer and they told me to bring they car back into them they would have to run a diagnosis test to tell me what is wrong with it. They told me that something else is wrong with the car because new cats do not just go.
Ok, suppose their work comes with a guarantee. The cat for sure does. Something else besides the cat causing a P0420 could be a failure of the installation of the cat causing an air leak near the before or after O2 sensor. Additional the sensor/sensor installation/connector/wiring could be causing P0420. I would let them run a diagnosis as a follow up/comeback(no charge to you) and let us know what they come up with.
Things that can effect longevity of cat converter: Verify that fuel trims are normal. Not more than plus/minus 10 at all engine loads. Verify oil consumption normal.