h22 accord failed smog
look it up in helms, but I think you use a vac pump and watch it lift or ohm it outwith a DVOM (DMM).. but dont remember off the top of my head... You might be able to clean out the passages with carb cleaner
What is the stock timing for a H22? If the timing is too far advanced it will increase combustion chamber pressure/temps and will increase NOx. CO and O2 and CO2 are close but HC and NOx are high.
Input of HC, CO, NOx, O2;
Reduction: NOx + CO > N2 + CO2
Oxidization: HC + CO + O2 > H2O + CO2
Even with new ignition components a slight misfire will cause an increase NOx emissions, combined with plugged EGR system the NOx will increase substantially.
Clean EGR system, verify the EGR valve works exercise it manually through its full range. That means taking it off and moving the valve with your fingers or a tool to push it open, tap the valve with a hammer.
Verify all your ignition is in operating condition. And make sure your base timing is correctly set. This seems to be the largest mistake most make with emissions testing. No point in going to test if your ignition is off, depending on who you take it to they may fail you on wrong timing alone even if the gas output is withing acceptable limits.
Input of HC, CO, NOx, O2;
Reduction: NOx + CO > N2 + CO2
Oxidization: HC + CO + O2 > H2O + CO2
Even with new ignition components a slight misfire will cause an increase NOx emissions, combined with plugged EGR system the NOx will increase substantially.
Clean EGR system, verify the EGR valve works exercise it manually through its full range. That means taking it off and moving the valve with your fingers or a tool to push it open, tap the valve with a hammer.
Verify all your ignition is in operating condition. And make sure your base timing is correctly set. This seems to be the largest mistake most make with emissions testing. No point in going to test if your ignition is off, depending on who you take it to they may fail you on wrong timing alone even if the gas output is withing acceptable limits.
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