How do you guys solve the P0420-430 CEl when you go catless downpipes?
- Thread starter Corleone1
- Start date
You Don't ...well that is to say you do... but you can ... if you want...because they don't happen, although they do... but only to some apparently in 100's of cases of kits fitted 
Has anyone ever told you that once you do tho' and if you ignore the CEL for a few days unless you have a scan tool to clear the CEL every time you start the car just incase... who knows for sure right?
That your turbo's will leak oil and your car will look like a diesel with a blocked DPF filter going down the hwy?
I fitted factory cats back to my modified 3" dump pipes and even with my std gay as aids bimodal exh back on the car, it still puffs here and there with cruise on or decelerating...
In general don't do it, or fit upgraded Ball Bearing turbos and re-route your coolant hoses and just shove your exh thru the bonnet for maximum woooosshhyyy noises... in general just go nuts... wooooooooooooooo
Has anyone ever told you that once you do tho' and if you ignore the CEL for a few days unless you have a scan tool to clear the CEL every time you start the car just incase... who knows for sure right?
That your turbo's will leak oil and your car will look like a diesel with a blocked DPF filter going down the hwy?
I fitted factory cats back to my modified 3" dump pipes and even with my std gay as aids bimodal exh back on the car, it still puffs here and there with cruise on or decelerating...
In general don't do it, or fit upgraded Ball Bearing turbos and re-route your coolant hoses and just shove your exh thru the bonnet for maximum woooosshhyyy noises... in general just go nuts... wooooooooooooooo
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It's a sore subject for me, i had 100cel dump pipes and tried 3 different sets of cat foolers finally i managed to own a car without a CEL every time i was slow cruising but then the smoke started and then the light came back on 
... so i spent the national debt and fitted factory cats and now i'm up to around 2000km's since the last engine light illuminated (i can prove this with my scan tool logs)it also hasn't gone into overboost for well over a month.
I honestly believe these MY23 cars were not meant to be mucked with !!
... so i spent the national debt and fitted factory cats and now i'm up to around 2000km's since the last engine light illuminated (i can prove this with my scan tool logs)it also hasn't gone into overboost for well over a month.I honestly believe these MY23 cars were not meant to be mucked with !!
Corleone1
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Sorry to say but the smoke is from over rev turbos. As turbos is small and fast they will over rev at shifts and if you use cat free DP;s you need to have a retune of ECU, JB tune wont make that work. Otherwise boost will increase by rev and also by gear and you can easily reach 30 psi at peaks. Neither engine (pistons) or turbos will take that.
About results to go catless DP;s... you get a lot of more power at higher revs like over 4000 rpm and also you can reach top power with less boost. I would say that 18 psi will make same power as 21 psi with full cats. I will dyno later this year but it really feels a lot of more response and top end.
P0420-30 is solved now. Thanks for inputs!
About results to go catless DP;s... you get a lot of more power at higher revs like over 4000 rpm and also you can reach top power with less boost. I would say that 18 psi will make same power as 21 psi with full cats. I will dyno later this year but it really feels a lot of more response and top end.
P0420-30 is solved now. Thanks for inputs!
So how did you solve it brother ?
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