Code: PO420...Need Help with Code

[alfben75]

Hello fellow Ford Explorers. I received a check engine light this afternoon that detemined a catalyst efficiency low-bank 1. I'm wondering if my explorer needs new oxygen sensors or do I need to replace a few catalytic converters. I need additional info before I tear apart my explorer. Thanks.

 

[Doubt Incarnate]

there are only 2 cats (on the v6 anyways), as to what one is bank 1 i dunno. to check for efficiency they run an o2 sensor before and after each cat, the after sensor is supposed to check that all emmisions are being burned in the cat. so it is telling you 1 cat is bad. i'd check the sensor wire first and make sure it is undamaged. I always check things first and then clear codes to see if they come back.

 

[Diggman33]

Me too...

Hi -
I have the same code (PO420) on my 97 Sport, 4.0L SOHC. The only thing the shop told me was that the message translated to "CAT BELOW THRESHOLD"... whatever that means, but Im sure it means big $$$.

I also noticed this nasty smell lingering in my cab - kind of smells like something burning on a BBQ grill is the best way I can describe it.

Prior to the code and the smell, my Explorer had a rough idle, and really bad fuel economy (more than usual). So Im betting it's all tied together somehow.

Let us know if/how you fixed the PO420 problem.

Thanks,
Steve