I have one of the original UR HFCs (ceramic) and I did get the SES. Sparkplug antifoulers took off the day to day SES, but if I run on the rev limiter (autox) for a few seconds, I can get it to come back on (secondary o2 sensor code -- not the same as when I didn't put the fouler on).

The new design has the same o2 fix as the test pipes, so no more SES.

Have the perrin.... CEL has come on every 100 miles. I'm just going to go catless in a few days.

Does anyone have the AMS HFC? I'm curious if it will bolt up to my Buschur Catback and stock downpipe, and whether or not it will throw a CEL.

I think this has alot to do with the car and each installation. These cars are very finicky when it comes to throwing the the 2nd O2 sensor cell. It doesnt mean the cat or pipe you purchased is bad by any means. The codes that you pull just tell you basically that the pipe is flowing much better. I also think there can be an installation issue with the difficulty in getting the stock O2 sensor off the car. As hard as it is I think they may be easily damaged, but maybe unrecognized in some cases. I do not think just cause your test pipe or high flow cat throws a cell from flowing better that it is a poorly made product.

Hey guys!
Its seems this might be something that comes up on some cars and not on others. When testing our car, we first used 2 cats(like the stock one has) then removed one and found ZERO power difference when making 330-ish WHP. Even with the one not installed, our car never had a PO420 code. That is not to say others will not! The newer cars in general can be finicky!

We have a couple options to help those with the CEL. 02 sensor extendors, and eventually the AP can deal with them. dcasandman has the extenders on the way to him to test out, so we will see how that goes! But if anyone else has a CEL with our catpipe, please call us and let us know what the code is and we can go from there!

I have a test pipe for sale that will not throw a code. The test pipe just needs to have the o2 sensor out of the exhaust stream. PM me if interested, sell for cheap, I don't need it anymore since I have a down pipe that eliminates that piece and I am running autronic

Now that's what I call "Good customer service"; standing behind their products!

Later, Ken
AMS Intake&Exhaust
Iveytune (322 all around; dynojet)
Robispec K&W

^^^I agree that's why I do most of business with these guys. The customer service is always awsome, and I think the rationale is sound. Im going to wait to get my tune with the AP on the 12th to see if it takes care of the cell issue before I go through the headache of messing with the O2 extender. Im hoping the custom AP tune will solve the Problem

Do you own an X?

I would spend the money in some other place. if you look at AMS Evo X, they have a turbo kit on it and noticed no power loss when putting a cat back on the car. I wouldn't even worry about it personally.

Less hassle with the cops as well....

how do know if your car has a cel? and the solution is getting a o2 spacer and if so who makes universal o2 spacers?

HKS Part number for the Evo X catalyitic converter. FYI:

P/N: 33005-AM003

they can make the cel go away with the AP {thumbup**

Ya going catless really doesn't help, but make your car stink! We have some tests done with 1 or 2 cats and even no cats on 400WHP Subys and they really don't do anything. Except make you a little more legal!

CEL is Check engine light. The term gets thrown around a lot so that might be why you said that. If you do have a Check Engine Light, you will see it on the dash. Then you need to have the code read to figure out what its for. Don't just guess its for a bad cat or not running one at all.

The first run of the AP's are not able to do this. But very shortly you will see this option.

Jeff, when you say, " We have some tests done with 1 or 2 cats and even no cats on 400WHP Subys and they really don't do anything." What do you mean by "anything"? No change in whp or no change in emmisions? With respect to the latter, they obviously are doing something since you say a car that is "catless" "stinks".

Later, Ken