Does anyone have any thoughts and price guestimate for sensors/conveter repairs? Thank You!

Question

The CEL on my 6 cylinder 05 Kia Sedona has been coming on and off for a little over a year.

I've taken it to get the codes checked out several times and they read the O2 sensors ( I can't remember the exact code #'s). All of the service locations zero'd out the codes, told me to drive the van 60 miles or so and bring it back if the CEL comes back on.

The first time I took it in the CEL didn't come back on for 8 months, the other times for a couple of months or a few weeks.

In April I took it in to a friend of my father's. He said after he took out the codes and drove it around for a week he thought the sensors and Cat Coverter were fine.

It's been several months since it came back on and that was for 2 weeks then off again. I got an an oil change 4 days ago and this morning the light came back on.

I took it to O'Rielly's to check the codes and today the code was P0420 Bank 1 below threshold.

My questions are:

What might have caused the CEL on and off issue?

Could the difference in codes presenteded earlier from this morning's code mean the earlier promblem was fixed?

If it is the O2 sensors and/or converter what is a guestimate of the repair costs? (in or around Greensboro, NC if possible)

Thank you! Suzanne

Answer 1

P0420 Catalytic below threshold Bank 1

In this case a datastream from a scantool will need to be used such as the fuel trim reading and when a P0420 occured, When the CK ENG LT comes on there is a freeze frame with data , this data is important to determine why a CK ENG LT occured, If you post the freeze frame data the exact cause can be known