hey guys,

my moms jag recently had a P0420 code. I replaced the cat with one from eastern and the code came back on. i then replaced the rear o2 sensor and again it came back on. i cleared the code both times.

when i replaced the converter however, i couldnt get the rear end of the pipe to slide in, so stupidy, i shrunk it a little with a tight clamp and some hammer tapping.... then it leaked. i then expanded it a bit and it still leaked but barely. i then filled it in with high temp silicone, and i think the leak is gone. the leak is behing the converter before the silencer and muffler.

wondering what you guys think could be causing this code. she has a rejection sticker now and its almost due. i also just cleaned what i belived was the MAF sensor. didnt clear the code or drive far after this though.

 

anybody?

 

Did you check/change the front O2 sensors? P0420 - Bank 1 Cat Converter - You did change the cat converter on the passenger side, yes? Also, I would get that high temp silicone out of there - get a muffler shop to straighten out that connection to the resonators - never heard of the eastern cat converter not properly fitting into the resonator pipe... Good Luck..

 

i changed the drivers side converter and the rear o2 sensor on that side. not the front o2 sensor. i was under the impression it was the rear that threw the code. the silicone is still there and does not leak. id like to fix the issue before spending the time money and effort of having that pipe expanded. it doesnt leak, and IMO theres no issue. what else can cause this issue? there is no head gasket leak, but i think the car burns a little oil.

 

tony, bring the cat to an exhaust shop. Let them properly fit the cat and seal all exhaust leaks. Did you inspect the stock cat. Though a cat code was thrown, this doesn't necessitate a failed cat, as Failed O2 sensors can implicate a cat too.

 

Um... P0420 is the passenger side cat converter!

Looks like you changed the wrong one! Hence why the P0420 code is still there..... (Read Post #3)

(P0430 - bank 2 - driver's side cat converter)

 

you've got to be kidding me......

where do you get that info? id like to see the source out of curiosity (not because i dont believe you). its just that everything i read said the lower number code was the drivers side, and higher was passenger.... for instance P0420=drivers side, and P0421=passengers side. and also, for o2 sensors, bank 1 is left side, sensor 1 is front.....?????????????

 

It's in the HowTo (such as Vehicle Spec...) and posted here fairly often. Also an International Standard, which jag followed properly from 2003MY USA.

Over here, bank 1 is driver side.... note where I am...

It's always RHS where the R is like in RHD.

I expect JTIS also says as much.

sorry, but no not kidding you

 

Dang! A rare case of "Sidus Inversus" (reversal of installation).

 

Sorry to be the bearer of bad news... +1 to what JagV8 already pointed out...

Regarding USA vehicles - bank 1 is passenger side and bank 2 is driver's side

P0420 (passenger)
P0430 (driver)

 

that is horrible. ugh! maybe i will try putting my (apparently) good rear (spare) o2 sensor into the other side to see if that gets rid of the code before buying another converter

 

hi all,

IM BACK!

so i still have this issue on my hands, mainly because i dont think its the converter, and i have too many projects on my hands....

but anyways, the car is leaking echaust up where the converter pipe meets the manifold. it looks like a donut gasket/flange mate, but the donut part is part of the manifold. i dont know why this is leaking.... any thoughts? i have tried putting high temp rtv on it and the leak is weaker but still there. i think (and hope) that this is causing the code.... becuase i now have a conver code, egr code, and an o2 sensor code. i tried a known good o2 sensor downstream and still get the code. could these all be caused from the leak? any tips on fixing the leak?

 

I'd kinda hope any competent exhaust shop could just do it right. Yeah it'll cause problems if it leaks. I bet the back pressure is wrong.

 

thanks jag- i will get the leak fixed at some point and report back!

 

bought a new converter for that side and it fixed the leak... and the light went out on its own

 

Good news!

 

Good job Tony! Thanks for reporting back as it really helps with future problems knowing how you got it fixed.
.
.
.