the nox is to hi it is 18.58 had a hi flow catalytic converter put on it. it was a hi flow one and it was 3.84 the new one was a regular one the next day it was higher to the 18.58nox level what can i do now please help? the engine has Les then 6000 miles on it. its not a bad engine is it?
2007-10-11 16:52:06 · 4 answers · asked by bigboy44mag 1 in Cars & Transportation ➔ Car Makes ➔ Chevrolet
no its not a bad engine,but was it bored out or anything that would cause it to run more compression,that could affect the levels your seeing from it,i got one of their 350,s and its bored and has a cam in it,and it doesn't run that high,that engine should be broken in good too,id try having it scanned real good,and see if anything comes up on a scanner,you may have a bad throttle body on it causing it to load up,it shouldn't run no where near that high,something is causing it to load up,if you have a scanner run the scan on it at different times,and see what happens to it,it may change from the time it gets hot to a cooler time,that's about all i know to tell you ,except make sure the timing is set exactly right on it,that will affect it a lot,mine runs real good and clean so yours should also,i have a throttle body injection,but try testing it a different temperatures and see if it changes,good luck with it.
2007-10-11 17:05:45 · answer #1 · answered by dodge man 7 · 0⤊ 2⤋
I own a shop, and have many years experience in dealing with computer related problems. This could be the engine has not seated the rings good, and won't run right until it gets a few miles on it. I doubt this is the case, but it could be. Your answer is within the exhaust, or a vacuum leak somewhere. Use a propane torch (do not light it), and move it around the engine until the engine speeds up, and you have found the leak. Check the intake to engine area, as the intake may not be sealing good to the heads. You may have to tighten the bolts some more, as this is a common problem with these engines. Take a good look at your ignition timing, and realize; the lower the timing, the hotter the engine will get, thus the cleaner it will burn. The O-2 sensor is before the catalytic converter on yours, so I don't think that would be your problem, but a leaking gasket in the headers allowing it to suck air into the exhaust will sometimes do this. Is your engine idle speed hard to get a handle on? If so then it does have a vacuum leak somewhere. I wouldn't rule out a leaking injector, or carburetor with a float level that is too high. Also suspect the wrong thermostat in the engine. In order for it (the computer) to make the right adjustments, you must have at least a 190 degree thermostat, or the engine will not get hot enough to burn clean. Also; is the temp sensor working as it should? Is the EGR valve sticking partically open? Are the vacuum lines in the proper places? When you go for the test, lower the ignition timing, run the crap out of it, and get the engine hot as you can, and it should pass with flying colors. I have see an engine with all the smog stuff unhooked pass the test! Put some clean burning fuel in the vehicle too such as 94 octane Amaco or BP. Finally you may want to suspect you have a bad O-2 sensor, or one that is out of range, and/or the spark plug gap needs to be increased to .045" for a hotter spark.
Glad to help out, Good Luck!!!
2007-10-12 03:44:51 · answer #2 · answered by Anonymous · 1⤊ 0⤋
No its definatly not the engine. First thing to check is the timing (I beleive it goes at 0 degrees). Second check to see if the EGR valve works and third check your fuel filter if it is resticted it will make it run to lean, And any lean condition will cause high nox emissions.
2007-10-11 17:04:54 · answer #3 · answered by bdiym1 3 · 1⤊ 1⤋
Does the engine have all the required emissions equipment on it ? I don't know what state you are in so don't know the requirements.
2007-10-11 17:05:37 · answer #4 · answered by tronary 7 · 0⤊ 1⤋