p0420, primary o2?
08-30-2015, 06:25 PM
#26
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Re: p0420, primary o2?
Maybe this will help in deciding your next move:
Before Checking a Catalytic Converter DTC:
Before you troubleshoot an OBD II vehicle that stores DTC P0420 (67) (catalyst system efficiency below threshold), run these quick checks:
1. Check for a leak in the exhaust system. If you find one, repair it, clear the DTC, and test-drive the vehicle.
• If the DTC doesn’t come back, return the vehicle to the customer.
• If the DTC returns, go to step 2.
2. Connect the PGM Tester, and test-drive the vehicle while an assistant monitors the voltage signal from the secondary oxygen sensor (HO2S S2). After the catalyst reaches operating temperature, the HO2S S2 voltage should stay between 0.5 and 0.8 V at steady cruising speed. During deceleration, the voltage should be steady at 0.1 V or less.
• If the voltage readings are OK, clear the DTC, and return the vehicle to the customer.
• At cruising speed, if the voltage fluctuates or stays below 5 V, go to step 3.
3. Measure the inlet and outlet external temperatures of the catalytic converter with a thermometer capable of reading up to 500°F.
• If the outlet temperature is more than 100°F hotter than the inlet temperature, the converter is OK; clear the DTC, and return the vehicle to the customer.
• If the outlet temperature is less than 100°F hotter than the inlet temperature, replace the converter.
Before Checking a Catalytic Converter DTC:
Before you troubleshoot an OBD II vehicle that stores DTC P0420 (67) (catalyst system efficiency below threshold), run these quick checks:
1. Check for a leak in the exhaust system. If you find one, repair it, clear the DTC, and test-drive the vehicle.
• If the DTC doesn’t come back, return the vehicle to the customer.
• If the DTC returns, go to step 2.
2. Connect the PGM Tester, and test-drive the vehicle while an assistant monitors the voltage signal from the secondary oxygen sensor (HO2S S2). After the catalyst reaches operating temperature, the HO2S S2 voltage should stay between 0.5 and 0.8 V at steady cruising speed. During deceleration, the voltage should be steady at 0.1 V or less.
• If the voltage readings are OK, clear the DTC, and return the vehicle to the customer.
• At cruising speed, if the voltage fluctuates or stays below 5 V, go to step 3.
3. Measure the inlet and outlet external temperatures of the catalytic converter with a thermometer capable of reading up to 500°F.
• If the outlet temperature is more than 100°F hotter than the inlet temperature, the converter is OK; clear the DTC, and return the vehicle to the customer.
• If the outlet temperature is less than 100°F hotter than the inlet temperature, replace the converter.
09-01-2015, 04:47 AM
#27
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Re: p0420, primary o2?
Despite what you think it's seriously hard to find used tsx stuff and with our dollar being .25 under the USD ebay isn't really an option. If I could unbolt it and bring it to them like that I would, i'm not looking to drop another 200+ in if it prevents me from getting the price I want maybe then I'll get another magna-flow one. i'd just likr a quick 24hr fix persay.
Again. 90 degree angle defoulers are more effective. But try the straight one from a parts store first. See if the CEL turns off/stays off. You may have to reset it.
I've used the trick for test pipes (S2000s and B series cars of various years) and HFC's (ITR & GSR). I've also used it on cars with borderline failing cats until I could replace them.
FYI...its way easy to use a cut off wheel to cut off the bolts to remove the cat. For the car I worked on (164K miles in Chicagoland), I used a 6 point, 11mm socket and a hammer to bash it onto the nuts that were previously 14mm heads (LOL). Then I used an impact to quickly zap them. I got half of them off that way. Used no heat because I ran out of mapp gas previously...and was too lazy to get more gas. I cut and air chiseled the other nuts/bolts.
I've done all of the above with the exhaust installed on the car. And I've done it by just removing the two 12mm flex pipe-to-header bolts, slipping the exhaust off the hangers (use soapy water or tire shine...not WD40) and getting the exhaust out in the open. The latter is easier.
These rusted bolts have no idea who they are dealing with.
09-01-2015, 05:16 AM
#28
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Re: p0420, primary o2?
An O2 defouler should fool the secondary O2 sensor into STFU'ing. It works for test piped cars.
Again. 90 degree angle defoulers are more effective. But try the straight one from a parts store first. See if the CEL turns off/stays off. You may have to reset it.
I've used the trick for test pipes (S2000s and B series cars of various years) and HFC's (ITR & GSR). I've also used it on cars with borderline failing cats until I could replace them.
FYI...its way easy to use a cut off wheel to cut off the bolts to remove the cat. For the car I worked on (164K miles in Chicagoland), I used a 6 point, 11mm socket and a hammer to bash it onto the nuts that were previously 14mm heads (LOL). Then I used an impact to quickly zap them. I got half of them off that way. Used no heat because I ran out of mapp gas previously...and was too lazy to get more gas. I cut and air chiseled the other nuts/bolts.
I've done all of the above with the exhaust installed on the car. And I've done it by just removing the two 12mm flex pipe-to-header bolts, slipping the exhaust off the hangers (use soapy water or tire shine...not WD40) and getting the exhaust out in the open. The latter is easier.
These rusted bolts have no idea who they are dealing with.
Again. 90 degree angle defoulers are more effective. But try the straight one from a parts store first. See if the CEL turns off/stays off. You may have to reset it.
I've used the trick for test pipes (S2000s and B series cars of various years) and HFC's (ITR & GSR). I've also used it on cars with borderline failing cats until I could replace them.
FYI...its way easy to use a cut off wheel to cut off the bolts to remove the cat. For the car I worked on (164K miles in Chicagoland), I used a 6 point, 11mm socket and a hammer to bash it onto the nuts that were previously 14mm heads (LOL). Then I used an impact to quickly zap them. I got half of them off that way. Used no heat because I ran out of mapp gas previously...and was too lazy to get more gas. I cut and air chiseled the other nuts/bolts.
I've done all of the above with the exhaust installed on the car. And I've done it by just removing the two 12mm flex pipe-to-header bolts, slipping the exhaust off the hangers (use soapy water or tire shine...not WD40) and getting the exhaust out in the open. The latter is easier.
These rusted bolts have no idea who they are dealing with.
09-03-2015, 04:36 PM
#31
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Re: p0420, primary o2?
Had the battery out/disconnected several times while cleaning the bay so far it's stayed off, it's been very hot/dry so maybe that helps. Either way I think I can get away with just unplugging the battery an hour before someone comes to look at it, i'm going on 500 km's since the last disconnect and no light. Thanks for the suggestions and hope I don't have to use them, not about to sink more in the car.
09-04-2015, 06:13 AM
#33
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Re: p0420, primary o2?
Had the battery out/disconnected several times while cleaning the bay so far it's stayed off, it's been very hot/dry so maybe that helps. Either way I think I can get away with just unplugging the battery an hour before someone comes to look at it, i'm going on 500 km's since the last disconnect and no light. Thanks for the suggestions and hope I don't have to use them, not about to sink more in the car.
09-09-2015, 09:19 AM
#35
Honda-Tech Member
Re: p0420, primary o2?
I couldn't' read all that back and forth BS, but I did this:
"spark plug non-fowler / o2 spacer installed between the exhaust bung and the rear o2... save yourself a few $$ and buy a few years."
This worked perfectly, I got the L shaped one for clearance. No CEL for 2 years until it was time to smog and then I had to buy a new cat.
"spark plug non-fowler / o2 spacer installed between the exhaust bung and the rear o2... save yourself a few $$ and buy a few years."
This worked perfectly, I got the L shaped one for clearance. No CEL for 2 years until it was time to smog and then I had to buy a new cat.
09-09-2015, 05:23 PM
#36
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Re: p0420, primary o2?
I couldn't' read all that back and forth BS, but I did this:
"spark plug non-fowler / o2 spacer installed between the exhaust bung and the rear o2... save yourself a few $$ and buy a few years."
This worked perfectly, I got the L shaped one for clearance. No CEL for 2 years until it was time to smog and then I had to buy a new cat.
"spark plug non-fowler / o2 spacer installed between the exhaust bung and the rear o2... save yourself a few $$ and buy a few years."
This worked perfectly, I got the L shaped one for clearance. No CEL for 2 years until it was time to smog and then I had to buy a new cat.
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