HC ppm
CO %
NO ppm

I know what they all stand for. What I am looking for, is what faulty device on the car would cause one level to be too high. I am trying to pass emissions and I am desperate.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by VTEC-DA &raquo;</TD></TR><TR><TD CLASS="quote">HC ppm
CO %
NO ppm

I know what they all stand for. What I am looking for, is what faulty device on the car would cause one level to be too high. I am trying to pass emissions and I am desperate.</TD></TR></TABLE>
Post your numbers.

 

----------------Limit--------Result
HC ppm--------97-----------312------Fail
CO %----------.54-----------5.54------Fail
NO ppm-------749---------697---------Pass

What do you all think?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b20guy &raquo;</TD></TR><TR><TD CLASS="quote">
OK JV, here you go... This is a suggested order for NOx failure of things to check:
1. EGR System
2. O2 Sensor
3. Timing/Spark Advance
4. Catalytic Converter
5. Incorrect/faulty thermostat
6. Coolant Temp Sensor may be open
7. MAP Sensor
8. MAF Sensor
9. Other sensors/switchs (uhhh yeah, ok)
10. Fuel Injection System
11. Faulty On-Board COmputer
12. Computer PROM
13. Internal Engine Repair

High HC Failure:
1. Spark Plugs and Wires
2. Timing Spark Advance
3. Vacuum Leaks
4. Other Ignition Problems
5. O2 Sensor
6 Evaporative fuel system
7. Fuel Injection System
8. Air/Fuel Mixture Adjustment
9. PCV System
10. Catalytic Converter(s)
11. Throttle Position Sensor
12. MAP Sensor
13. MAF Sensor
14. Other Sensors/Switchs (dohh, again)
15. Computer PROM
16. Internal Engine Repair

High CO Failure

In the case of carb engines, up to 85-86
1. Choke System
2. Carburetor Repair

In the case of fuel injected engines, from 1986 on,
1. Fuel Injection System
2. Induction system problems
3. O2 Sensor
4. TPS
5. MAP
6. MAF
7. Coolant Temp Sensor may be closed
8. OTher sensors/switches (I guess this is a CYA thing (cover your ***)
9. Valve train problems
10.Jumped engine timing belt
Plus...
Idle speed adjustment
Air Filter Condition
Thermostatic Air Cleaner
Air Injection/Reaction System
EVAP fuel system
Oil and Filter Change
Catalytic Converter
Computer PROM


That's it in a nutshell... We had a 91 Maxima today that failed for NOx, while the HC and CO readings were great. We began diagnosing what might be the problem. First thing we told him was that cylinder 5 plug was crossthreaded and not seated properly. Also, the injector on that cylinder was bad. Unfortunately he declined the repair and paid the checkout. I really wanted to see if that cylinder being dead was the cause for the high NO, but maybe when he gets it fixed and returns, things will be fine.

As far as your car goes, maybe the O2 sensor needs replacement, even if there is no check engine light.

Let us know what your attempts are...and I hope this helps a little.
</TD></TR></TABLE>

taken from this thread...

https://honda-tech.com/zerothread?id=544598

 

thanks man

 

You have a bunch of unburned fuel
check for misfire
high hc can also be causing the high co
are you throwing any codes?

 

When I took the test I wasnt. Now I am throwing a 41 because of my shitty Bosch o2 sensor.

 

Try this product out it owrked for me in california, and i was labled Gross polluter, which is as bad as you can get here http://www.passsmog.com/

 

HCs are raw fuel. I would check your airfilter. A clogged airfilter will cause HCs to go up, along with a fouled plug. Just do a tune up. and CHANGE the oil. That makes a difference belive it or not