What causes high nox on smog test?
02-22-2013, 07:48 PM
#1
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Car: 89 Iroc
Engine: 305 TPI
Transmission: 700R
What causes high nox on smog test?
My car failed twice because of this high nox thing can some one please help me out? I got it diagnosed and it came back that my egr was bad so I replaced egr and nox reading were higher they went from 700 to 1030?
Last edited by Calixbwsx; 02-22-2013 at 08:02 PM.
02-22-2013, 09:27 PM
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Re: What causes high nox on smog test?
Nox is from high combustion chamber temps - timing, EGR, engine temp (thermostat). If you replaced the EGR was the passages clear of carbon deposits. Ty to pull up on the diaphragm of the EGR and your engine should die or just about die. If very little to no idle change your passage is carbon blocked. What are your other readings CO2 and HC readings
02-23-2013, 09:10 AM
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02-24-2013, 09:33 AM
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Car: 89 Iroc
Engine: 305 TPI
Transmission: 700R
Re: What causes high nox on smog test?
I was actually checking and the vacuum line was disconnected I plugged it up and boom passed the test.thanks fellas
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