So I've searched all over and i'm having trouble sifting through everything.

I have an 04, 95K miles...just got a CEL yesterday - P0420 (bank 1 - cat system efficiency below threshold). I took it up to my shop, they did a check - want to replace 02 sensor, cats and do a fuel system clean for $1500!!!

I called a few dealers and they recommended i didnt go to them - they said all i needed was a muffler shop to cut out the old cat and weld in a new. They said with that code 99.9% chance its a bad cat and not the o2 sensors. But I've read that it could be the sensors too.

But then i read that the universal cats these places weld in can be crappy and not last...so I started researching the magnaflow cats, and those answers are all over the place. It seems like the 94106 is the recommended one. There is a 94136 which has the bungs already in place.

Any help? I am due for inspection this month and it wont pass with the CEL. So I need to do something, but I want to do it right - i want it to last, not throw a CEL, and hopefully not cost me $1500. One muffler shop said parts and labor was about $400 (much easier to digest).

Please help

 

Go with an aftermarket Cat...

But...the consensus is that something caused the Catalytic converter to go bad..ie bad fuel injector, misfire, bad plugs...so that should be fixed in conjunction with the cat...

 

Is the 04 subject to the fuel injector recall? If it is a bad injector, then the cat will be free from Ford.

Might want to do a little homework before you put a new cat on it.

 

No, only certain 05's were subject to the injector customer satisfaction program (NOT a recall).

Doesn't the 04 have 4 cats?

 

2004 appears to be the same 4 cat setup as the 05...thank the lord you are not in California...OEM is the only alternative for the 05's...at least 04 there are aftermarket choices.....