Failed Emissions Test, Help....

[thepremier]

Man I just failed my emissions test today. I had a feeling that it might happen, but I was hoping that I would be relieved, and I obviously wasn't.

Here are the test results:

1. Gas Cap Check (Pass)

2. EVAP Components (Pass)

3. Hydrocarbons (Fail)
My Car registered at:2.50 (g)
State applicable: 1.60 (g)

4. Oxides of Nitrogen (Fail)
My car registered at: 3.43 (g)
State applicable: 2.50 (g)


From reading the numbers, what should I have done to my car so that it will pass the 2nd test.

I know for a fact that I need to have the spark plug wires connecting to the correct spark plugs. I had a feeling that they weren't in the correct sequential order, and when the guy at the emissions gave me the list of problems that I may be having, one of the reasons was the problem I just mentioned.

Other problems could be the catalytic converter, etc... I'm sure you guys know more about this stuff than me, so I am asking advice as to what I should be looking to have repaired before my next test.

All advice is appeciated.

Thanks

 

[87geeinn]

I'd think you'd know it if your spark plug wires weren't connected to the correct plugs. Do you have a catalytic converter on the car now? What chip are you running and does your EGR valve/system function?

 

[thepremier]

I'd think you'd know it if your spark plug wires weren't connected to the correct plugs. Do you have a catalytic converter on the car now? What chip are you running and does your EGR valve/system function?

What I mean by the plug wires and the plugs is that they may be out of order. When new spark plugs were put in, I forgot to remember the order, so it took me forever to figure it out. I thought I finally figured it out because the engine sounded good when I strated it up and kept it running. That's why I was thinking that it could be one of the problems. There is a catalytic converter on the car, I'm not sure if it's any good, how would I be able to tell if I need a new one? This car was pretty much given to me, from a relative that has too many cars to say the least, so I'm not sure if there is a chip in it but I don't think there is any aftermarket chip. As for the EGR valve/system, you'd have to explain to me what I would be hearing or seeing if it was function good or bad. I do know that my boos gauge doesn't work anymore, if that even means anything.

Thanks for the response

 

[Marc87GN]

I was surprised to see the HC high and the NOx because usually the additional fuel lowers the combustion chamber temperatures and the NOx comes down. I believe you want to use a scantool and make sure all of your numbers (BLMs, O2s, etc) are in good order.

The EGR is not your problem because I just passed NYS dyno emissions on 6/19 with exactly how my car sits with everything in it. I lowered the FP from 45-40 and the guy ran the car in 3rd. The NOx limit was 2.00 and my car was 0.40 with the Extender chip installed so the EGR is not your problem. I have a 3" ATR cat installed with only about 4K miles on it so I know it works well. Your cat may not be working correctly because you blew out of the ranges. Check the plugs, wires, use a scantool, and try a different cat.

 

[steveX]

Turbo car are less likly to pass gas emmsion test. It is strongly advisabe to perform a FULL tune-up before doing exhaust gas test. I believe by changing PLUGS,WIRE,PCV,EGR valve/manifold passage way,O2,injector cleaner,crankcase flush,air filter,clean TB,NO vacumme leaks,check Fuel press, and NO oil leaking into the induction system. Your HIGH HG reading you have "X" amount of un-burn gasoline in the exhaust, not much. changing the spark plug, and O2 sensor will correct this issue.

 

[steveX]

You should also remove the EGR valve from the intake manifold and CHECK the passage way for carbon blockage. You can check the passage way by blowing hi-PSI air through the passage way. The EGR control NO2 level. With your current reading you should have no problem PASSING this time around. GOOD LUCK

 

[LETHAL-6]

I had high readings on my T . All I did was lower fuel pressure and passed without any problems. Good luck.

 

[gofstbuick]

Since the HC and NOx is high, and you suspect the firing order in incorrect, fix the firing order first. Is the coil pack stock? If it is, the firing order in on the coil pack, just below the spark plug wire boot. Like Steve says, make sure the engine is in correct tune. Misfires will break the substrate in the cat, so when the misfires are repaired and the vehicle barely fails, your next move may be a cat.

 

[JSAautomotive]

I was surprised to see the HC high and the NOx because usually the additional fuel lowers the combustion chamber temperatures and the NOx comes down. I believe you want to use a scantool and make sure all of your numbers (BLMs, O2s, etc) are in good order.

Without seeing the CO (carbon monoxide) readings, you don't know if the high HC (hydrocarbon) readings are as a result of excess fuel in the combustion chamber or if it's just misfiring. So the high HC readings usually don't lower the NOx readings in a scenario like that.

ThePremier..... Please post your CO, O2, and CO2 readings also please. This will give us a better picture as to what exactly is going on.

The high HC readings would indicate there may be a misfire occuring. Does the engine miss or buck on acceleration?? Does the engine idle smoothly and normally?? If either is a problem, I would suspect your firing order, plugs, wires or even coil pack to be a problem. Should be checked out.

Your high NOx is due to excess peak combustion temps. Either the EGR isn't working, or your CO is VERY low. The high NOx and HC readings may also be due to a worn out or defective cat. But I'll need the rest of the readings to determine this.

John

 

[Marc87GN]

Without seeing the CO (carbon monoxide) readings, you don't know if the high HC (hydrocarbon) readings are as a result of excess fuel in the combustion chamber or if it's just misfiring. So the high HC readings usually don't lower the NOx readings in a scenario like that.

ThePremier..... Please post your CO, O2, and CO2 readings also please. This will give us a better picture as to what exactly is going on.

The high HC readings would indicate there may be a misfire occuring. Does the engine miss or buck on acceleration?? Does the engine idle smoothly and normally?? If either is a problem, I would suspect your firing order, plugs, wires or even coil pack to be a problem. Should be checked out.

Your high NOx is due to excess peak combustion temps. Either the EGR isn't working, or your CO is VERY low. The high NOx and HC readings may also be due to a worn out or defective cat. But I'll need the rest of the readings to determine this.

John

I agree. I was under the assumption that people wouldn't bring a misfiring vehicle to get an inspection because it doesn't go unnoticed. I'm not sure that the EGR does very much on a low compression engine when not under alot of boost during the inspection. My GN has passed both times with low NOx numbers with the Extender chip in and the EGR off, but I have a working 3 way cat.

 

[Hacksaw]

With high HC & NOx I would also wonder about carbon build up boosting compression.