Do Cats go bad? Failed smog.
Thread Starter
Melting Slicks
Joined: Jan 2004
Posts: 3,138
Likes: 37
From: Burbank. CA.
Do Cats go bad? Failed smog.
I believe I have Random Tech high flow cats. They came with Kooks headers. They have been on the car for about 3 months. The car failed smog and the tech guy said he thought the cats were bad. Based on how slow the numbers were coming down to pass.
I have a cam 220/224 581 114 lsa, Blackwing and Kooks. The car has a great tune in it.
Any suggestions?
Steve
I have a cam 220/224 581 114 lsa, Blackwing and Kooks. The car has a great tune in it.
Any suggestions?
Steve
Drifting
Joined: Jun 2004
Posts: 1,627
Likes: 143
From: Goodyear Az
In general terms, to help pass smog make sure you have:
1) A fresh oil change -- hydrocarbons get trapped in the oil.
2) A fresh set of spark plugs -- obvious... better burn, less emissions.
There is some anectodal evidence that says high-flow cats simply don't remove unburnt hydrocarbons as well as stock cats -- and that's partly why they have higher than stock flow.
1) A fresh oil change -- hydrocarbons get trapped in the oil.
2) A fresh set of spark plugs -- obvious... better burn, less emissions.
There is some anectodal evidence that says high-flow cats simply don't remove unburnt hydrocarbons as well as stock cats -- and that's partly why they have higher than stock flow.
Safety Car
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From: Vette-hid.com Lost in DFW texas
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St. Jude Donor '06-'07
Originally Posted by mountainbiker2
Yes.
Advanced
Joined: Jul 2004
Posts: 53
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From: Oakdale Ca
Hey Steve, I have the same cam (115 lsa), headers, RT cats, and use the same tuner as you. I haven't had to have my car smoged yet but am interested in what you find out. We met at Andy's last year when you had your gears installed. Hope that you find a good solution.
Jeff & Mutt
Jeff & Mutt
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Joined: Jul 2002
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From: Sterling VA
What do they test for there? Obviously hydrocarbons and carbon monoxide. Do they test for NOx? If not, see if you can get your tuner to tweak it to run a little lean for the test. The HC and CO will go down, but the NOx will increase.
Also, are you running a low temp thermostat? If so, go back to stock, the higher temps will be better for emissions.
Also, are you running a low temp thermostat? If so, go back to stock, the higher temps will be better for emissions.
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Brett Foote
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From: Schaumburg IL
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St. Jude Donor '06-'10, '13
Originally Posted by nuke61
There is some anectodal evidence that says high-flow cats simply don't remove unburnt hydrocarbons as well as stock cats -- and that's partly why they have higher than stock flow.
I believe this is your problem. I have the check engine light on and code P0420 which is a cat effciancy code...in other words the stock rear O2 sensors are telling the computer the high-flow cats are not burning enough emissions off. I think LS1 edit can fix this...but you mention you already have a tune, plus your dealing with the sniffer test....too bad you can't just get by with OBDII where they just plug in the your computer and check the readiness and codes 
good luck
Last edited by FrankTank; Jun 15, 2005 at 02:38 PM.
Racer
Joined: Jul 2004
Posts: 285
Likes: 5
From: Palos Verdes California
Hey Steve,
What was the water temperature on the car? Maybe the fans are coming on too early. Also, maybe your oil cooler isn't allowing the oil to get to a temperature that's hot enough to allow the car to burn off whatever it's passing through the tail pipes. Just a guess. Hope this helps.
What was the water temperature on the car? Maybe the fans are coming on too early. Also, maybe your oil cooler isn't allowing the oil to get to a temperature that's hot enough to allow the car to burn off whatever it's passing through the tail pipes. Just a guess. Hope this helps.
Last edited by crznZ06; Jun 15, 2005 at 04:48 PM.
Thread Starter
Melting Slicks
Joined: Jan 2004
Posts: 3,138
Likes: 37
From: Burbank. CA.
Thanks guys. I'll keep you posted.
Water temp. 190
Oil temp. ? Probably to cold.
Did get a special tune for smog. It helped but not enough.
Plugs almost new.
Fresh oil.
Steve
Water temp. 190
Oil temp. ? Probably to cold.
Did get a special tune for smog. It helped but not enough.
Plugs almost new.
Fresh oil.
Steve
Last edited by mountainbiker2; Jun 15, 2005 at 05:17 PM.
