yes - I think I have learned a very expensive lesson if I cannot get it on warranty. Will most definitely keep you all posted. At least some other novice can learn from my mistakes. If I known that it was leaded gas I put in - of course I would not have done it. But it was not labeled of course - I thought all gas was unleaded now-a-days. What is ironic about that is that the person filling it up (some old lady) put it in after I actually asked her if its okay. She said you will be fine. But really - I am the one to blame for being so stupid.

 

Sure you will be fine but what about the car?

I sure hope Porsche covers that but lead on cats is very obvious. So prepare yourself.

It's a bummer for sure.

Anything over 100 has to have lead to get the kick. It's like an old guy with a young girl. He's going to need a boost somewhere!!!

I learned that last year at the FXX at Infineon. There was 117 octane there in the pits!

Best of luck.

 

yeah check your plugs too. you did not do anything bad... its just cats get eaten alive by leaded race gas.

 

That's not true - there are commercial gasoline blends with octane 100+ without lead.

 

Wow I did not know that!

Well that means there's hope for me with younger women!

Somebody years ago told me to get the lead out of my a@@, and I did! I thought I would need a boost.

You have made my day for sure.

 

We have unleaded 101 at the pump at one or two stations in WA 24hr self serve. That is plenty of detonation resistance for most modified car, and probably a waste of money for stock. The only way you will get away with not replacing the converters is to run it up to temp driving for awile to hopefully blow some of that lead out. Your best bet is to make lemonade out of your lemons. Get the aftermarket exhaust you’ve always wanted! If you get the stock exhaust from the dealer it will probably end up costing more then some of the aftermarkets. Many owners who upgrade their exhaust hang onto them in case they ever want to change back but you could get lucky and snag one for a good deal. After you get the exhaust figured out, and you drove it for a little bit to get rid of most of the lead, you will need to replace both up stream and downstream sensors, for each bank, and replacing the plugs is a good Idea too. Converters don't go bad without a reason. You dealer will know what's going on as soon as they turn the key.

 

btw. how would I know my converter is bad ?. I dont have any loss of power really and there seems to be no blockage or anything. Maybe I have just fried the o2 sensors ? no ? Right now I am only getting a sensor reading that says the car is running too rich - or something like that. The check engine light is not flashing (thought that was a good/better thing).

 

Octane rating works with engine compression ratio and ignition timing.
Air/Fuel mixture is important for proper timing detonation.

Higher compression outputs whether NA or via boost require ignition timing retardation to avoid engine pinging/knocking and piston damage. This is why high octane (slower burn) gasoline is used.

You should only use the recommended fuel octane rating for your setup.
Using a higher octane than 93 in a stock setup is wasting your $$$ and fouling
your catalyst,O2 oxygen sensors, and fouling your plugs...

Some states are using an Ethanol mixture. (10% maximum.) Pure gasoline w/out the Ethanol is better if you can get it...
than the same octane rating with Ethanol.

 

Just FYI,

My cat related CEL has gone on twice now, and each time it went off by itself after a couple of days. The dealer did a readout saying the fault was due to "decreased catalytic converter efficiency". The service advisor said this is something they have seen on occasion with hi-flow (aftermarket) cats like mine (AWE).

Pain in the butt, but likely not doing any damage. It would be nice if your condition can also be self-remedied by blowing some of the lead out of the cats, as in "Get the lead out!"

 

You may need a new set of cats too.

 

I think your cats and plugs are toast. I run unleaded 100 octane in my car most of the time. My ECU adjust to the the octane when run. The differance with the ECU and fuel is night and day. My friend made the same mistake you did and it was cats and plugs. Good luck let us know how things work out.

 

BTW Chris, I got another CEL yesterday - this is my 3rd set of Cats! I'm starting to lose my patience.

 

That's got to be frustrating. I'm running a Europipe system with 100 cell cats and have never had a problem. The way Europipe explained it to me had to do with the size of the sport cats in relation to the OEM cats. Below is what they said. I don't pretend to understand the science/engineering but I thought it was interesting.

- A stock 997 TT exhaust uses 600 cells.
600 cells per square inch or about 24.5 cells per inch / 25.4 mm
24.5 cells horizontal x 24.5 cells vertical = 600 cpsi
- We use Emitec cats not HJS cats.
There are other good quality German catalytic convertor manufacturers besides Emitec too.
HJS is not a catalytic convertor manufacturer.
Our Emitec cats are coated specifically for our 997 TT exhaust application.
HJS cats come in just one type of coating ( precious metal coating )
- We use Emitec PE perforated foil cats. Conventional cats have just an axial flow pattern while the Emitec PE cats will flow axial ,
diagonal and radial. So no problems with the approach angle of our
inlet cone , the exhaust gasses will spread evenly inside the cat which results in lower backpressure.
- Our 153mm diameter cats have twice the cross section of the commonly used 108 mm cats.
The airspeed inside the 153mm cats is just half of the airspeed inside 108mm cats so the backpressure is lower too.
- The 100 cpsi cats will create less backpressure than higher density cats of the same size. ( same diameter + length )

 

E55AMG,

What brand of exhaust are you running?

 

O2 sensors are after the cats as they monitor the activity w/in the cats.

This, unfortunately, may not be good news because it appears the O2 sensors are working but the cats are not!

Ugh.

I hope not.

Keep us posted.

BTW, you should see M3 S3R's turbo coupe! Now that's a beauty! And he has had an ECU update that allows him to run and maximize 100 octane.