I just want to share my experiences. I own a 2007 997 TT with a chipped ECU and a high performance exhaust system, name brands. The ECU is programmed to handle 100 octane fuel. While watching a track event I loaded a half tank of Sunocco 100 unleaded fuel. About 2-3 weeks later now on normal pump 93 octane fuel I received check engine light. It happens now on a regular basis. Resetting the error code only to have it reappear within 20 miles, (code P845) I've been told that the catalytic converters are wiped out due to the high octane fuel. The coating have been striped off.

A set of experiences all of you who have gone the same route should be informed about.

Because the cat are welded in the only way to solve this problem is to replace the +$4000 exhaust system or go back to stock

 

1. Cut off old cats.
2. Weld on new cats.

 

You could have a shop weld on new cats instead of replace whole system.

What brand exhaust is it?

997tt are notorious for throwing CEL's with modified exhausts... My guess is poor cat quality...

 

Ok where can I purchase a new set of cat 100 or 200 cell german made 3" pipe

 

HJS 100-cell metal cats

 

Was the gas unleaded?
if so then it shouldn't affect your cats.

Edit: oops! I saw that it was unleaded gas.

That's odd since I've never heard of unleaded gas harming the cats.

 

What brand exhaust system is it?

 

I don't want to get into mud slinging on the forum. My intentions are to get some advice , maybe get them reworked but let others know of the situation that the folks selling the equipment never tell you

 

Bad Bruno bad!!

 

AWE I think sells 100 cell Cats on their website.

 

I've use race gas many times and have not had this problem. I have the GIAC software and aftermarket exhaust also. You should go back and talk to the manufacture of your exhaust. As long as the race gas you used was unleaded, it shouldn't be your fault.

 

Be Careful Qs997Turbo !!

 

That sounds terrible, but your could always do as my fellow 6speeder here recommends. That's pretty amazing because I had a similar set up on my B5 S4 back in the day and ran 100 octane fuel quite a bit with no problems (that I know of today any way).

 

thanks for your suggestions everyone, what about suggestions on where to get the Cats, I'll call AWE in the morning...

 

I'll go back and check if it was leaded or unleaded fuel the pumps are right next to each other.. What does leaded fuel do to the cats?