Check engine

[Sporter]

Hi.
I have a 2007 jeep srt8.
when I install 91 tune or 93 tune I wil get a check engine light after some driving.
When I read the intune it states that a catalytic converter is not funktioning right.
I can clear the code and it can be fine fore some days but then it will turn up again.

Tere are no other mods on this car.
Any ideas why this is happening?

[mikel]

what code is it exactly?

[Sporter]

Thank you for your atentione.
I had the Jeep to a exhaust shoppe and they fixed some gaskets, after that I loded the 91 tune back in and there has no check engine light and no code shown yet.

BR
Sverrir

[Sporter]

Right after my last post the light came back on, the code is P0420 catalyst system efficiency below threshold.
If I remerry the Jepp it does not come back.

[mikel]

it would seem you have a bad drivers side cat...

[Sporter]

Ewen tho the light/code never shows when the Jeep is in stock tune?
He is only driven 17000 miles.

[Mike_Levy]

Modded SRT8s eat through cats. I replaced both of mine on my Jeep twice. 17k is high. My first change occurred at 8800 miles, and the second set at about 17k.

[Sporter]

Ok then the time is now to eliminate them
Thanks and best regards
Sverrir

[Mike_Levy]

Eliminating them will cost you about 30hp. Tried that before the second replacement. The Hemi likes some backpressure.

[Sporter]

Oh ok then Ill get som new ones soon, I dont want to lose 30 HP.
After I saw this post I want to try and tune it and see if I can get rid of the light before I buy som new cats.
http://www.cherokeesrt8.com/forums/show ... ight=P0420

We have lower grade gasoline then you do In the US, could it not be that the code is coming because of the tune is not sutible?
But then agen onlie on one bank.

Thanks
BR
Sverrir