HELP! 93 Accord-Failed NO emissions test. What now?
Joined: Oct 2004
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From: WAZZU, WA, United States
Re: HELP! 93 Accord-Failed NO emissions test. What now? (tander123)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by »</TD></TR><TR><TD CLASS="quote">» Search Results
Your search for Emission returned 12 results.</TD></TR></TABLE>
Try the seach button. It's probobally eithor a bad o2 sensor or clogged EGR ports.
Your search for Emission returned 12 results.</TD></TR></TABLE>
Try the seach button. It's probobally eithor a bad o2 sensor or clogged EGR ports.
Honda-Tech Member
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From: New England, USA
Re: HELP! 93 Accord-Failed NO emissions test. What now? (tander123)
Hondas are known to have restricted or blocked exhaust gas recirculation (EGR) passages. I looked at reasons for a NOx failure, including the inputs Honda uses to control EGR operation. High NOx emissions are caused by excessive heat due to high combustion chamber temperatures.
Causes of high combustion temp:
1) The cooling system. This system needs to be in proper working order or the engine can run hot, which can elevate NOx emissions.
2) Incorrect timing or spark advance.
3) Carbon deposits in the combustion chamber.
4) Incorrect spark plug heat range.
5) Incorrect vacuum to the EGR valve. First check codes in the engine control module (ECM). In most Hondas, if it has an EGR problem it will set a code. Tee a vacuum gauge into the vacuum line to the EGR valve and test-drive the vehicle, verify a vacuum signal to operate the EGR valve.
Start here.
P
Modified by P_Adams at 5:13 AM 3/4/2006
Causes of high combustion temp:
1) The cooling system. This system needs to be in proper working order or the engine can run hot, which can elevate NOx emissions.
2) Incorrect timing or spark advance.
3) Carbon deposits in the combustion chamber.
4) Incorrect spark plug heat range.
5) Incorrect vacuum to the EGR valve. First check codes in the engine control module (ECM). In most Hondas, if it has an EGR problem it will set a code. Tee a vacuum gauge into the vacuum line to the EGR valve and test-drive the vehicle, verify a vacuum signal to operate the EGR valve.
Start here.
P
Modified by P_Adams at 5:13 AM 3/4/2006
B*a*n*n*e*d
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From: Bouncing off of the city bus in Saigon
Re: HELP! 93 Accord-Failed NO emissions test. What now? (P_Adams)
actually I'd go for cleaning the EGR valve and passages first.
Long before the car will toss a CEL, it will have some hesitation between 1500-2500 rpm.
Since it is a '93, you will have to drill out the rivets that hold down the access plate for the EGR passages.
Long before the car will toss a CEL, it will have some hesitation between 1500-2500 rpm.
Since it is a '93, you will have to drill out the rivets that hold down the access plate for the EGR passages.
Honda-Tech Member
Joined: Apr 2002
Posts: 7,574
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From: Cincinnati,, Oh
Re: HELP! 93 Accord-Failed NO emissions test. What now? (YeuEmMaiMai)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by YeuEmMaiMai »</TD></TR><TR><TD CLASS="quote">actually I'd go for cleaning the EGR valve and passages first.
Long before the car will toss a CEL, it will have some hesitation between 1500-2500 rpm.
Since it is a '93, you will have to drill out the rivets that hold down the access plate for the EGR passages.</TD></TR></TABLE>
It might be alot less time and effort to test the egr system first. Maybe there isn't anything wrong with it?
Long before the car will toss a CEL, it will have some hesitation between 1500-2500 rpm.
Since it is a '93, you will have to drill out the rivets that hold down the access plate for the EGR passages.</TD></TR></TABLE>
It might be alot less time and effort to test the egr system first. Maybe there isn't anything wrong with it?
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