wAt tHe ####?
Thread Starter
Registered User
Joined: Jul 2008
Posts: 36
Likes: 0
From: Vientiane
wAt tHe ####?
Yesterday my 03 SC S2K was running not so smooth and then the CEL (check engine light) comes up.. so i took it to see what's wrong since i try to reset the ECU for a couple of time and it wont go away.. the scanner read (p0141) Secondary Oxygen Sensor is broken, the hold tip of the sensor broke off because the catalytic converter filter push all the way to the back.
The tip of the O2 sensor is stuck inside the catalytic converter. So the mechanic advice me to removed it by cutting the catalytic converter open and removed all the filter out of it and wait for the O2 sensor to replace. The car still got CEL and driving with CAT but No filter inside.
Modification;
2003 S2000 17,000 Miles
Comptech supercharged NOVI1000 aftercooler, ACT CLUTCH KIT, HEAVY DUTY PRESSURE PLATE, Gear Ratio to 4.57. HKS Dual Hi power exhaust/ TEIN dress up string, Defi gauges and the rest are Carbon fiber hood, hardtop, ADVAN Model 5 17" rims. Spoon Strut Bar
My questions:
1. Why&How did the filter inside the CAT can move so far back to cut off the head of the O2 sensor? when the tip still looks new when we recover it...
2. The performance will increase or decrease when driving with the CAT but no Filter inside and will it effect the O2 sensor to brake again after replacing with a new O2 sensor (Emission test is not an Issue in LAOS)
3. Can I go race on track when CEL is one because my O2 sensor will arrived after track day (order parts from USA takes 2 weeks) or is there any other alternative ? should or should not?
The tip of the O2 sensor is stuck inside the catalytic converter. So the mechanic advice me to removed it by cutting the catalytic converter open and removed all the filter out of it and wait for the O2 sensor to replace. The car still got CEL and driving with CAT but No filter inside.
Modification;
2003 S2000 17,000 Miles
Comptech supercharged NOVI1000 aftercooler, ACT CLUTCH KIT, HEAVY DUTY PRESSURE PLATE, Gear Ratio to 4.57. HKS Dual Hi power exhaust/ TEIN dress up string, Defi gauges and the rest are Carbon fiber hood, hardtop, ADVAN Model 5 17" rims. Spoon Strut Bar
My questions:
1. Why&How did the filter inside the CAT can move so far back to cut off the head of the O2 sensor? when the tip still looks new when we recover it...
2. The performance will increase or decrease when driving with the CAT but no Filter inside and will it effect the O2 sensor to brake again after replacing with a new O2 sensor (Emission test is not an Issue in LAOS)
3. Can I go race on track when CEL is one because my O2 sensor will arrived after track day (order parts from USA takes 2 weeks) or is there any other alternative ? should or should not?
Registered User
Joined: Dec 2007
Posts: 3,947
Likes: 8
From: Raleigh, NC
The SC probably cooked the honeycomb shut in places, and the back pressure eventually shoved it back. It may perform better if it was clogged too bad. I can't remember if the secondary o2 sensor causes limp mode, but I think you should be ok.
Registered User
Joined: Sep 2007
Posts: 666
Likes: 0
From: Germany - Spain
Originally Posted by lao_s2k,Oct 1 2008, 03:43 AM
3. Can I go race on track when CEL is one because my O2 sensor will arrived after track day (order parts from USA takes 2 weeks) or is there any other alternative ? should or should not?
but u "should not" (or better said "i would not")With the CEL on, the first thing you have to consider is that ECU will be running the whole time in Open Loop mode and it will ignore the info from the lambda sensor.
Thread Starter
Registered User
Joined: Jul 2008
Posts: 36
Likes: 0
From: Vientiane
Can anyone help me chose which part is correct because from the detail on all parts available it mention After or Before Catalytic but the one i need is directly on the Catalytic (secondary Oxygen sensor) so i am not sure which is the correct one.
http://www.oxygensensorwholesale.com/catal...003&No=0&Npp=10
please reply with the SKU number from the above website...
thank you
http://www.oxygensensorwholesale.com/catal...003&No=0&Npp=10
please reply with the SKU number from the above website...
thank you
Joined: Oct 2000
Posts: 9,210
Likes: 7
From: WA
This is a relatively common problem that has happened to many of us. Honda has replaced quite a few cats under the emissions warranty so I would try them for a new cat. I don't think performance is impacted by a failure of the secondary sensor so you should be able to track the car without problem. Just keep in mind that the failure will happen again with that cat so just replacing the sensor is not a long term fix.
Besides, I'm not sure that there is such a thing as an emissions warranty in Laos.
Trending Topics
Registered User
Joined: Jan 2008
Posts: 932
Likes: 1
Secondary O2 is after cat (it is 'downstream' of the exhaust gas flow).
It sniffs to see whether exhaust gas got cleaner after passing through the cat, as compared to the reading off of the primary (before cat ) sensor. If the gas is not 'cleaner' in secondary than in primary, then to the car computer it looks like the catalyctic converter (cat) is not doing its job, and the computer shows a code: like, 'Hey, replace your cat, the green tree-hugging hippies are not happy with the blatant disregard for our environment and greenhouse gases"
The honeycomb (you called it filter) got loose, was pushed by exhaust gases back, sheared off the secondary oxygen sensor.
So if you hollow out the cat, you will definitely see the computer give you a code. So you need to install the 'testpipe CEL fix'. Search for what it is.
It sniffs to see whether exhaust gas got cleaner after passing through the cat, as compared to the reading off of the primary (before cat ) sensor. If the gas is not 'cleaner' in secondary than in primary, then to the car computer it looks like the catalyctic converter (cat) is not doing its job, and the computer shows a code: like, 'Hey, replace your cat, the green tree-hugging hippies are not happy with the blatant disregard for our environment and greenhouse gases"
The honeycomb (you called it filter) got loose, was pushed by exhaust gases back, sheared off the secondary oxygen sensor.
So if you hollow out the cat, you will definitely see the computer give you a code. So you need to install the 'testpipe CEL fix'. Search for what it is.
Thread Starter
Registered User
Joined: Jul 2008
Posts: 36
Likes: 0
From: Vientiane
Originally Posted by Kirpich,Oct 1 2008, 08:17 PM
Secondary O2 is after cat (it is 'downstream' of the exhaust gas flow).
It sniffs to see whether exhaust gas got cleaner after passing through the cat, as compared to the reading off of the primary (before cat ) sensor. If the gas is not 'cleaner' in secondary than in primary, then to the car computer it looks like the catalyctic converter (cat) is not doing its job, and the computer shows a code: like, 'Hey, replace your cat, the green tree-hugging hippies are not happy with the blatant disregard for our environment and greenhouse gases"
The honeycomb (you called it filter) got loose, was pushed by exhaust gases back, sheared off the secondary oxygen sensor.
So if you hollow out the cat, you will definitely see the computer give you a code. So you need to install the 'testpipe CEL fix'. Search for what it is.
It sniffs to see whether exhaust gas got cleaner after passing through the cat, as compared to the reading off of the primary (before cat ) sensor. If the gas is not 'cleaner' in secondary than in primary, then to the car computer it looks like the catalyctic converter (cat) is not doing its job, and the computer shows a code: like, 'Hey, replace your cat, the green tree-hugging hippies are not happy with the blatant disregard for our environment and greenhouse gases"
The honeycomb (you called it filter) got loose, was pushed by exhaust gases back, sheared off the secondary oxygen sensor.
So if you hollow out the cat, you will definitely see the computer give you a code. So you need to install the 'testpipe CEL fix'. Search for what it is.
bUt...
i look for the test pipe but shipping cost oversea would be very expensive since it look heavy, can i have an exhaust shop custom made it (stainless steel) with an hold to fit the new secondary O2? would it work the same as order it from Invidia test pipe online ? will the primary O2 pick up CEL with the custom made pipe?
Driving with CAT without honeycomb isn't it the same as a straight custom made pipe?
Registered User
Joined: Jan 2006
Posts: 710
Likes: 0
Indeed, You will need to have the secondary o2 moved out of the flow of the exhaust. Search o2 CEL fix on ebay and see if you can find something similar at a hardware store around your area. The muffler shop that makes your test pipe might be able to make the o2 cel fix too..