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Hamze 03-29-2010 09:02 AM

P0420 trouble code
I've had that trouble code ever since i've bought my 3.7L V6 Laredo, and my Check Engine Light is always on.....

This code means : Catalyst System Efficiency Below Threshold (Bank 1).

I've replaced all my 4 O2 sensors, and the code still appears after a few hours of driving. I now know that i have a problem with my catalytic converters ..

I am planning to delete my converters,and run pipes. I must trick my ECU that there are still converters in there..... i've did some research for O2 OXYGEN SENSOR SIMULATOR.... and Or, O2 OXYGEN SENSOR ELIMINATOR kits, i found 3 types which are the following:




My Question is : Is anyone running those on their jeep? do they work ? are they safe? are they Cr*p ?

I Hope that they work :) .. any help appreciated!

robpp 03-29-2010 09:17 AM

Re: P0420 trouble code
the srt8 have had NO LUCK with those.

some have had luck with the o2 spacers, mostly 06 and earlier. you buy these spacers, they also put some steel wool around the o2 tip. and some can get past codes about no cats.

like this hamze

Hamze 03-29-2010 01:28 PM

Re: P0420 trouble code
Thanks Robpp for the awesome info !! now i will research those spacers my brother! :)

robpp 03-29-2010 02:40 PM

Re: P0420 trouble code
yeah there seems to be some experimentation with some drilling a small hole in the spacer as well.

I read about this on srt8 site. i will search to see what details I can find on the jeep.

robpp 03-29-2010 02:48 PM

Re: P0420 trouble code
here are thedetails brother.

if anyone else is wanting to try this mod, I used 4 Help! # 42002 Spark plug non-foulers, 2 of them I drilled with a 31/64 drill bit, and the other 2 I did not modify. I installed the un-modified non-foulers into the O2 sensor bungs on the exhaust using never-seeze on the threads, I then lightly packed the non fouler with 00 Stainless steelwoo. I only packed the area below the threads, and it is loosely packed, not jammed in there. I found that I still got a CEL when I drilled the non-foulers with a 1/2" drill, so I bought another set and drilled them 31/64" I chucked them up in my lathe and bored the hole to make sure it is perfectly centered, as there is not alot of clearance to the O2 sensr, and I did not want it grounding out or rubbing against the non fouler. The only difference compared to the write up on the Charger forums is the hole is smaller, it is only 1/64" smaller, but it seems to work so far. Like I said, be careful drilling out the hole, as you want it centered and straight. Good luck and I'd appreciate any feedback. Murf

and her is the parts he is talking about

Hamze 03-29-2010 03:25 PM

Re: P0420 trouble code
The nice thing in Our jeeps '' as what i've read while researching '' is that the rear O2 sensors have nuthing to do with the Air to Fuel ratio... A/F is controlled by the first post cat sensors, the rears are for catalist efficiency...

Non jeep forum though... but i Like the write up -->

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