Hello,

Looking for advice on what's causing my CEL to come on. Here's a little history:

1. received CEL
2. autozone scanned and returned P0420 code
3. replaced both 02 sensors with universal after market sensors
4. CEL still on
5. removed catalytic converter and cleaned by soaking overnight in
detergent (found this suggestion online)
6. had autozone scan again and this time got a p0131 and p0141
7. online search for code said bad 02 sensor in bank 1 (upstream)
8. replaced both sensors with denso direct connect
9. CEL no longer on. Drove car for 45 mins or so before CEL returned

I guess at this point I will have the car scanned again to see if the code is different. However, before doing that does anyone have any idea why the CEL returned? Will I probably have to replace the catalytic converter?

Thanks,
Troy

 

I have no idea why the code returned. You should figure out the code first before making any assumptions.

 

Had Autozone scan the car again and this time the p0420 returned. Sounds like the old Cat needs to be replaced. I replace the old cat and the CEL is off again. Drove the car for about 30 mins with no CEL return. Car also appears to have more power. The big test is the drive to work tomorrow. Hopefully the combo of the new O2 sensors and the cat converter corrected the problem. I will keep my fingers crossed;-)

 

CEL still off. The car was due for inspection, so i got that taken care of today. All is good.