Looking for feedback: Running 100 cell cats. Check engine light comes on, checked with OBDII scanner, results:
P0430: Cat efficiency below threshold. Bank 2. 1 of 2
P0420: Cat efficiency below threshold. Bank 1. 2 of 2
When comparing the factory GT3 cats (400 cell?) against these 100 cell cats, of course they should flow / clean exhaust differently. Are these bad or is the motronic just doing what it is supposed to? Plan on GIAC re-flash soon. Will this address issue?
Thanks in advance.

 

What kind of cats ? If the coating used by the aftermarket cat mfg'r does not match the chemical coating of the porsche 400 cell cats, it's quite possible. I was concerned when I went with them. Europipe. Stef assured me that the coating on the stock ones was analyzed and that forumlation was used for his cats. No probs yet for me. He even warranties his exhaust cats against failure (CEL light) for 2 years I think....

 

Rockitman,
You are the man! So far I have used your very helpful DIY for the exhaust and the Euro seats, Thank-you. Purchased the GEMBALLA Power kit (Headers, connected X-crossed 100 cel cats and mufflers) from a fellow 6Speeder. I would have hoped that GEMBALLA be more helpful however, did not think to ask about the chemical composition.

 

There is a washcoating deposited on all catalytic converters that is propietary. You cant send it out an have it analyzed by a lab. basically the 100 cell cats PUT you at risk for a CEL dummy light for 2 reasons... 1) the surface area the exhaust makes contact with is much smaller 2) the time the exhaust is on the surface is reduced given the reduced backpressure. Gemballa would have to cut-out and replace the cats to trurn off the CEL or either ignore the CEL light or remove the code in the computer. If you have to tolerate the CEL anyway............get catabypass pipes and really really WAKE up the GT3.

best regards
Joe Fabiani
Fabspeed Motorsports
www.fabspeed.com
info@fabspeed.com

 

Fellow 6Speeders,

I have found an easy, fast and inexpensive fix to my check engine light (cel light) issue. What is more unbelievable is that it is easy, inexpensive, you can DIY and is reversable. Did not want to pursue an electrical fix by splicing into the cel harness and adding some kind of capacitor or resistor. After resetting check engine light, have driven over 100 miles and no cel light!

You need to purchase 4ea. Anti-fouler spark plugs. They are packaged 2 to a pack so, you'll need to purchase 2 packs. Cost @ $4/pack. I found these at the neighborhood NAPA auto parts store. Part # 730-2443. These actually a 18mm spark plug spacer designed to move a spark plug further out from the combustion chamber for older FORD's that burned oil. It is not some kind of special spark plug.

1. You'll have to do a little machine work to fit your 2nd. 02 into this Anti-fouler. With the help of my dad and his metal lathe. Take 1ea of the Anti-fouler (AF) plug and insert a 19/32 drill bit into the AF. From this point you will drill out .175 of the AF (.125 = 1/8" - .250 = 1/4"). BE VERY CAREFUL not to drill too deep as you will ruin the AF by coming out of the threaded part on the other side!
2. Once you have successfully bored out the AF. Take this same AF and drill all the way through with a 15/32 drill bit.
3. Now assemble before installing on exhaust pipe as you don't want to over torque and ruin the precision work you did in step 1.
Take the newly machined AF and screw into the back of the other AF that came in the package. Next take your 02, coat with anti-seize and screw into the back of the machined AF.
4. Coat other AF with anti-seize and insert into exhaust bung and torque down.

I believe that this solution moves the 2nd 02 sensor out of the direct hotter exhaust stream enough to fool the engine check light so it falls back into a closer to stock fuel trim range of .2-.8 Volt range. Someone can chime in at this point if my thought of why it works is slightly off. What I can confirm is since installing, have driven the car in city traffic, highway cruising and full throttle red line (Open and close loop engine situation) and no dreaded cel light!

I'll bet that this will also work if you decide to run a cat bypass pipe...

Good luck!

 

Pics, pics, pics....

 

Daryl, Very resourceful there!! I'm sure youll sort out the rest of the bugs.

 

I found a guy that did the same but on a Evo MR:

STEP 1
-purchase 2 spark plug anti foulers at your local auto parts store
-18 mm size
-made by HELP brand / part number 42002
-HELP has also another part number 42009 and are shorter in length than the 42002, i have heard they worked , but i am not 100 percent





STEP 2
-disconnect the negative terminal on your battery. this will reset your ecu
-take one of the anti foulers and drill out its center using a 1/2 bit ,
-this will increase its hole size and allow your stock o2 sensor to fit








STEP 3
-screw the drilled spark plug anti-fouler on top of the original
-be sure to use some kind of anti-seize on the treads. in case you need to remove your fix with ease






STEP 4
-unscrew your stock o2 sensor and place your cel / ses fix in
-use anti seize on the threads
-clean your cell (by wiping it off with a paper towel)







STEP 5
-reinstall your o2 sensor
-use anti seize on the threads






STEP 6
-reconnect your battery (your ecu is reset)
-you have just solved the problem of the 'damn light keeps coming on'




ps. its cost me 8 dollars for the pack of 2 spark plug anti-foulers

 

Great post. If my europipe cats burn out, I will try this. let us know if the light comes back on anytime soon. Sounds like you got the fix though. Well done !

 

Chris,

how many miles do you have on your Europipe? Does Europipe sells just the cats?

Thanks

 

Tiago,
Thanks for adding the pix to illustrate the steps however, would caution all to be careful while drilling/boring the Anti-fouler (AF). Illustrated example is 02 from a EVO MR, the Porsche 02 is sized slightly different! Should you use too large of a drill bit and / or go off center you stand the chance of ruining the treads on the AF and it will not screw into the back of the stock AF. (Who enjoys going back to the parts store in the middle of a job, even if it is a $4 part?)

 

this works, i can verify using it also