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crazexr7
10-10-2011, 04:06 PM
my cats are going bad, probably since i replaced them with cheap ebay ones. anyways, i bought a new universal off ecs and it says its a pre-obdII. I took it to a mechanic to get a quote and he said it'll still run a CEL since its a pre obdII, but ecs says it should work. will this still run a check engine light if i install it? It's a cherry bomb universal 2.25", just want to make sure before i install

http://www.ecstuning.com/Audi-B5_A4-Quattro-V6_30v/Exhaust/Universal/ES4389/

csosnowski
10-10-2011, 05:21 PM
quote from ecs page: OBD II compliant universal fit catalytic converter.

cat is a cat imo, if you get a cel just run some defoulers.

crazexr7
10-10-2011, 05:27 PM
quote from ecs page: OBD II compliant universal fit catalytic converter.

cat is a cat imo, if you get a cel just run some defoulers.
cool thanks, the pre obd II thing on the packaging was throwing me off. I doubted the CEL would come on again but what the mechanic said made me worry i'd have to send it back again.

Corrado_Guy
10-10-2011, 06:42 PM
Most pre OBD-II cars did not have a post cat O2 sensor so this would be the only thing to look out for. If you have a welder you can get an O2 sensor bung and just weld it in on the rear of the cat if the replacement is missing it.

crazexr7
10-10-2011, 06:56 PM
Most pre OBD-II cars did not have a post cat O2 sensor so this would be the only thing to look out for. If you have a welder you can get an O2 sensor bung and just weld it in on the rear of the cat if the replacement is missing it.
the replacement is missing it but i was thinking of having the back pipe of the new one cut off and welding the preexisting bung welded onto the back of the new cat?

Corrado_Guy
10-10-2011, 07:28 PM
O2 sensor bungs are cheap and abundant, go to any car parts place such as (insert big name place here) and ask for them and just weld that in. It is much easier to drill a hole and weld a bung in than cutting off one pipe and then fit to the other hoping they are the same size and all that. You can probably get a bung at the same place you are getting your cat because they are common. When I swapped my car to OBD-II I welded in the bung for the second O2 sensor leaving the original in place....

http://media.corrado-club.ca/mods/images/obd_ii_conv/obd_ii_conv016.jpg

And then I started to get cels and I couldn't find an anti-fouler so I moved the front O2 sensor forward onto the downpipe and capped the original front sensor....

http://media.corrado-club.ca/mods/images/obd_ii_conv/obd_ii_conv019.jpg

I bought a bunch of these from either Summet or Jegs because they are always handy to have when you are making your own stuff.

crazexr7
10-10-2011, 07:35 PM
hmmm thanks for the info I appreciate it I'll have to check into it. I'll try and see if the place i'm getting the cat welded will have it or do it or look around.

walky_talky20
10-10-2011, 07:41 PM
Your mechanics worries are valid. Generally speaking, aftermarket catalytic converters are not loaded *nearly* as heavily with the magical precious metals that do catalytic business. Key point: this is *why* they are cheaper. Therefore, they do not perform their job as efficiently as the exceedingly expensive OEM piece. But this is all OK because that cat doesn't have to pass all the government tests for sale because it says "pre-obd2" on the package. Isn't that slick?

Moral of the story, aftermarket cats are not as good as OEM (where "good" = saving the earth and keeping your CEL off). They may keep the light off for a while, they may not. Key point being that they *are* doing something, so a spacer (defouler) on the rear O2 should be pretty effective at helping it out should the need arise. Good Luck.

crazexr7
10-10-2011, 07:54 PM
Your mechanics worries are valid. Generally speaking, aftermarket catalytic converters are not loaded *nearly* as heavily with the magical precious metals that do catalytic business. Key point: this is *why* they are cheaper. Therefore, they do not perform their job as efficiently as the exceedingly expensive OEM piece. But this is all OK because that cat doesn't have to pass all the government tests for sale because it says "pre-obd2" on the package. Isn't that slick?

Moral of the story, aftermarket cats are not as good as OEM (where "good" = saving the earth and keeping your CEL off). They may keep the light off for a while, they may not. Key point being that they *are* doing something, so a spacer (defouler) on the rear O2 should be pretty effective at helping it out should the need arise. Good Luck.
thanks, I'm going to need it. And yeah, really hard finding a good one for cheap, and CT takes emissions seriously too. This one has a warranty on it though unlike the ebay ones [headbang] but it's still cheap which scares me a lot. I don't know how well cherry bomb makes a cat.

Corrado_Guy
10-11-2011, 05:06 PM
Your mechanics worries are valid. Generally speaking, aftermarket catalytic converters are not loaded *nearly* as heavily with the magical precious metals that do catalytic business. Key point: this is *why* they are cheaper. Therefore, they do not perform their job as efficiently as the exceedingly expensive OEM piece. But this is all OK because that cat doesn't have to pass all the government tests for sale because it says "pre-obd2" on the package. Isn't that slick?

Moral of the story, aftermarket cats are not as good as OEM (where "good" = saving the earth and keeping your CEL off). They may keep the light off for a while, they may not. Key point being that they *are* doing something, so a spacer (defouler) on the rear O2 should be pretty effective at helping it out should the need arise. Good Luck.

My trick is to use two cats, one for emmssions testing and one for driving around the rest of the year. The pics above are from my Corrado and that is the high flow cat I run all year and this is the one I run for a few hours every two years....

http://members.shaw.ca/vr6_corrado/Test_Cat-3.jpg

My A4 doesn't have a cat so I don't know how this will fly with emissions testing, hopefully the Unitronic's software can fool it.

walky_talky20
10-11-2011, 05:59 PM
That's pretty slick. It will always pass emissions because the cat never gets any miles on it. And easy to switch out. Brilliant.

crazexr7
10-11-2011, 06:41 PM
that is really smart. And I talked to the mechanic and he said he'll weld a bung on for me so hopefully everything goes well, getting it put on tomorrow.

fusion28
05-07-2012, 11:53 PM
I got the CEL on my car. I got a B6 Audi A4 3.0 Q Manual. Stating that the Catalytic converter is burning too cold. So a sensor might be broken or I need to change it. Interesting enough, I took it into Audi and they stated that I don't have any issues. Now the CEL is on again... I don't really want to spend $1000 on one.. So what issues will I have in the future? If I have to spend $1000 on one for preventative care then so be it... But what issues will I have?

walky_talky20
05-08-2012, 04:20 AM
A: Post the *actual code* (ie: the number) you are dealing with. You have not done this.
B: Unless you have a mandatory emissions inspection that requires ALL monitors to pass and no Check Engine Light, then you don't even need to fix it.
C: If the above emissions test is only a computer test (ie: they only plug into the obd2 port, not a sniffer test), then you may be able to squeak by using a spacer on the rear o2 sensor. This fools the computer into thinking that your cat is working fantastic, even if it isn't. Hooray.
D: If you car is under 80,000 miles, there is a federal emissions warranty that should make Audi buy you a new cat (or 2) if they have failed.
E: This is the B5 forum. You should be in the B6 forum.