Well, last night driving home a buddy of mine said my car "smelled funny" while he was driving behind me, and sure enough a few minutes later my car threw a P0420 catalytic converter operating under efficiency threshold. It appears that my UR HFC has given up the ghost.

I have about 6-8k miles on it, and I'm definitely thinking that's a little soon for even a HFC to give out. has anyone else had issues with the UR HFC and CELs? i was running a cobb stage 2 map until just recently (Nov 28th) going to a GST tune. Other than probably running rich for a while, I haven't really done too much that would destroy the cat that I can think of...

maybe it's just time to get a test pipe.

 

Your cat shouldn't be toast after 10 miles, However, the CEL might be just from a more free running exhaust, get an O2 fix for your rear sensor and then you should be fine. And yes, running rich will destroy your cat, unburnt fuel eats the catalytic material.

 

The ECU may have just been tripped and the O2 sensor thrown because it recognized the exhaust gases were too unburnt.

You can reset the battery and see if it comes back, or just get a CEL fix off ebay. I did, it is just an extension for the sensor to take it out of the exhaust flow.

 

Was under the impression that UR had this issue solved on their HFC... no need to unplug the battery I can clear the code using software. Was more interested in whether or not other people had experienced this with the UR HFC

thanks for the info though! it's useful.

edit to add: running rich meaning the stock tune... afaik I haven't run any richer than that on any of my tunes, which isn't really saying much.

 

Does the CEL on the X say "service engine soon", cause that is what I am getting from my Artisan exhaust?

 

Yes, that's the CEL. Should be able to pull the code using a Cobb AP or Evoscan or really any OBD-II tool pretty easily which will tell you exactly what your ECU is complaining about.