po420
#1
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I have a 1999 Dodge Ram 1500 4x4 5.9L. I keep getting code po420. I know what this means, so here is my question. Does the code keep coming back because it is searching for the catalytic convertor? It has one but I busted all of the stuff out of it and put it back on because it was clogged. I have replaced both the pre and post o2 sensors. I keep clearing it with my scanner and after several days I get the code again. Sometimes a week or two may go by before it comes back on. The engine runs fine other than my gas millage has dropped which I have expected with no convertor. Any advice or suggestions would be greatly appreciated. Thank you
#2
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http://www.obd-codes.com/p0420
your computer is reporting that your gutted cat is not working properly. specifically, the rear O2 emissions readings are not lower than the front.
there's a couple of things you can try.
one is to install a spark plug non-fouling spacer to move the O2 a little farther out of the exhaust pipe. some have success with this.
the other is to remove the rear O2 and strap it up in open air. plug the hole. this works for others.
your computer is reporting that your gutted cat is not working properly. specifically, the rear O2 emissions readings are not lower than the front.
there's a couple of things you can try.
one is to install a spark plug non-fouling spacer to move the O2 a little farther out of the exhaust pipe. some have success with this.
the other is to remove the rear O2 and strap it up in open air. plug the hole. this works for others.