2011 Dakota Big Horn, 3.7L V6
CEL light continues to come on.
I have replaced the O2 sensor that is on the passenger side and downstream of the catalytic converter. Reset code, and it came on shortly thereafter.
I have done the best I can to check for vacuum, and exhaust leaks. Nothing jumping out at me.
All wiring to O2 sensor looks good. No damage.
If I reset the code, it will stay off until I drive at highway speed for 3-5 miles. As soon as I let my foot off the accelerator to exit the highway the CEL comes back on.
I have also reset the computer to rule out it throwing a stored code.
I am at my wits end with this and I am looking for any ideas I can get.
I have even taken it to a Dodge dealership and they tell me they can't even fix it. This all occurred when the vehicle still had a warranty on it. Pretty sure all they ever did was reset the CEL.
Please help!
Thank you.

 

When I look this up - possible causes.
*Oxygen sensor defective
*systems running very rich or lean
*engine misfire
*fuel pressure very high or low


Maybe there's a rich or lean condition happening when you let off the pedal.

 

How about back to the basics, have you checked for vacuum leaks?

 

fcastro, I am no expert mechanic....how does one check for vacuum leaks?

 

Hey redbird,
Here is a little information for you to test/diagnose with. Hope it helps.
http://dh.identifix.com/AssetDetails...tStructureId=1

 

Looks like that is a service you have to pay for? Not sure if you are a salesman for them, or if I am missing something???

 

Lets try it this way...Sorry.