CEL after kooks header install.
Thread Starter
5th Gear
Joined: Sep 2016
Posts: 5
Likes: 0
CEL after kooks header install.
I previously had an AWE track exhaust n kooks cats installed with no CEL. Recently I added the kooks headers and got a CEL after about 200 miles. Car seems to drive fine so I’m wondering what it could be. Going to bring it in to dealer next week but just wondering if anyone had any issues similar to this. Dealer was cool and said as long as issue is not due to the aftermarket parts they’d cover under warranty.
Thread Starter
5th Gear
Joined: Sep 2016
Posts: 5
Likes: 0
Not sure on the code. Tried getting from onstar but I guess I need to upgrade my plan. It’s a solid light not blinking.
not sure if this has anything to do with it but the dct Ota update had failed that morning. It never went through.
not sure if this has anything to do with it but the dct Ota update had failed that morning. It never went through.
Supporting Vendor
Joined: Feb 2020
Posts: 729
Likes: 350
From: Fort Washington, PA
Will be interested to hear the end result. The addition of the headers alone should not create a fault, as no emissions control devices are removed. It's likely too early for the Kooks cats to fail and throw P0420 / P0430. Hopefully it's just a loose connection with a sensor or something small. Keep us posted!
Melting Slicks
Joined: Jun 2012
Posts: 2,226
Likes: 1,029
From: Thomas Texas
Pulling a code is not too difficult. I have the Kiwi that plugs into the OBD-II port and connects via Bluetooth to my I-Phone. I downloaded a free app to my I-phone and gets all kinds of information include DTC codes.
My guess (and its a guess...) its the rear O2 sensors reporting cat inefficiency. Not anything bad, but nobody wants the check engine light glowing in your face. Also, the car will fail the annual inspection.
My guess (and its a guess...) its the rear O2 sensors reporting cat inefficiency. Not anything bad, but nobody wants the check engine light glowing in your face. Also, the car will fail the annual inspection.
Heel & Toe
Joined: Nov 2020
Posts: 15
Likes: 1
From: VA
full exhaust swap on mine... i've had P0420 i think 3 times in as many months. each time i erase the code it is the drivers side 02 sensor after the cat. i have swapped the sensor to the passenger side this week and see if it pops on again. so many things i think it could be. I'm 7 minutes from work probably not driving it hard enough and cats getting a bit backed up. who knows. It wont let you remote start the car if the cel light is on either.
Keep us posted thx
Keep us posted thx
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Supporting Vendor
Joined: Feb 2020
Posts: 729
Likes: 350
From: Fort Washington, PA
full exhaust swap on mine... i've had P0420 i think 3 times in as many months. each time i erase the code it is the drivers side 02 sensor after the cat. i have swapped the sensor to the passenger side this week and see if it pops on again. so many things i think it could be. I'm 7 minutes from work probably not driving it hard enough and cats getting a bit backed up. who knows. It wont let you remote start the car if the cel light is on either.
Keep us posted thx
Keep us posted thx
Supporting Vendor
Joined: Feb 2020
Posts: 729
Likes: 350
From: Fort Washington, PA
You couldn't have had them installed for too long or too many miles. What is their warranty?
Catalysts are a consumable part - only a finite amount of catalyst material can be contained in the core - which can only "scrub" a finite amount of exhaust. They should last for tens of thousands of trouble-free miles. Our Sport Cats come with a No Check Engine Light Guarantee, and a 5 year warranty to the original purchaser - including a one-time re-coring of the cat itself.
Intermediate
Joined: Oct 2019
Posts: 44
Likes: 30
Seems a bit outrageous to be forced to purchase another product to work around the Kooks cat failure?
You couldn't have had them installed for too long or too many miles. What is their warranty?
Catalysts are a consumable part - only a finite amount of catalyst material can be contained in the core - which can only "scrub" a finite amount of exhaust. They should last for tens of thousands of trouble-free miles. Our Sport Cats come with a No Check Engine Light Guarantee, and a 5 year warranty to the original purchaser - including a one-time re-coring of the cat itself.
You couldn't have had them installed for too long or too many miles. What is their warranty?
Catalysts are a consumable part - only a finite amount of catalyst material can be contained in the core - which can only "scrub" a finite amount of exhaust. They should last for tens of thousands of trouble-free miles. Our Sport Cats come with a No Check Engine Light Guarantee, and a 5 year warranty to the original purchaser - including a one-time re-coring of the cat itself.
Heel & Toe
Joined: Nov 2020
Posts: 15
Likes: 1
From: VA
UPDATE... Knock on wood, after installing o2 sensor extensions/ non mini cat style, and a long drive today both cruising and harder driving no p0420 cel. hope this helps.
Afe headers kook cats and awe track exhaust. yep my neighbors love me at 6 30 am.
Afe headers kook cats and awe track exhaust. yep my neighbors love me at 6 30 am.
Heel & Toe
Joined: Nov 2020
Posts: 15
Likes: 1
From: VA
so far the 02 spacers on mine have done the trick. non mini cat just spacers installed after the cats.
Supporting Vendor
Joined: Feb 2020
Posts: 729
Likes: 350
From: Fort Washington, PA
The whole idea of high flow cats is to make power while remaining "green" and emissions compliant. If the high flow cats work properly, no tune or O2 Spacers are required to kill a Check Engine Light. If the high flow cats are not 'scrubbing" the exhaust well enough to avoid a CEL, why not just save the money and go cat bypass instead if you're encountering all the downsides of cat bypass anyway?
Last edited by Fabspeed_Motorsport; Nov 23, 2020 at 08:47 AM.
Pro
Joined: Oct 2020
Posts: 697
Likes: 446
From: Wylie TX
Still confused as to why O2 Spacers would be required on what are essentially brand new high flow cats?
The whole idea of high flow cats is to make power while remaining "green" and emissions compliant. If the high flow cats work properly, no tune or O2 Spacers are required to kill a Check Engine Light. If the high flow cats are not 'scrubbing" the exhaust well enough to avoid a CEL, why not just save the money and go cat bypass instead if you're encountering all the downsides of cat bypass anyway?
The whole idea of high flow cats is to make power while remaining "green" and emissions compliant. If the high flow cats work properly, no tune or O2 Spacers are required to kill a Check Engine Light. If the high flow cats are not 'scrubbing" the exhaust well enough to avoid a CEL, why not just save the money and go cat bypass instead if you're encountering all the downsides of cat bypass anyway?
Supporting Vendor
Joined: Feb 2020
Posts: 729
Likes: 350
From: Fort Washington, PA
My point is thatO2 spacers should not be necessary if you're using a quality high flow catalyst or sport cat. The high flow cats themselves should keep the CEL out if engineered properly.