I needed to get my car smogged for registration purposes. And i went in thinking that everything would be fine. The car runs great and everything. But to my suprise it failed. In fact it failed so bad that it is labeled as a gross polluter. My question is what makes the HC levels go through the roof? I had to get it smogged a little over a year ago and the reading were in the 70's and now they are in the 1700's???!!!! Any help would be greatly appreciated..

 

ANYONE????

 

can u post your other gas readings they would help alot...list O2,CO2,CO and NOX

hc's is misfire

ignition system wires,plugs,rotor,cap..etc.. or
misfire due to running lean your nox would be high too

 

Here are the other readings:

15 MPH:

co2 14.3
o2 0.0
HC 117
co .72
no 52

25 MPH: this is where i had problems

co2 10.9
o2 4.1
HC 1788** max was 93
co 1.60** max was .63
no 584

so what do you guys think???

 

1. HYDROCARBONS (HC)

Hydrocarbons are unburned fuel. The presence of HC in the exhaust shows unused energy (fuel) going out the tailpipe.

Excessive HC in vehicles is the result of incomplete combustion, which could be caused by ignition malfunction, mechanical faults, vacuum leaks or fuel control or fuel management problems.

-----------------my guess would be to first check vacuum leaks, plugs (gap settings) wires, dizzy etc. Also running a fuel system cleaner through it will help and checking your EGR and catalyic converter...that high of a reading I would almost guarantee thats where most of your problem is coming from.

2. CARBON MONOXIDE (CO)

Carbon monoxide is formed when a hydrocarbon (like gasoline) tries to burn (oxide) in an oxygen poor environment. Only part of the energy in the hydrocarbons is released for useful power, the rest are not released energy because of poor combustion.

CO therefore is a by-product of combustion. Excessive CO is created when and only when fuel is burned without sufficient air (O2) to allow for complete combustion, also known as oxygen starvation.

--------------I would check air filter, possible o2 sensor

Does your car throw any CEL (check engine lights)?

 

Nope i have never seen the check engine light come on. So where do you thinki should start? New cat. converter?

 

I would first check the easy stuff:

plugs, wires, air filter but usually with that high of HC means a shitty cat, I would replace it. And run some fuel cleaner through I recommend bg44k .

Also your EGR might be bad...that usually depicts high reading typically HC.

 

Great thanks!! Where do i get this bg44k stuff??

 

http://www.storesonline.com/si...oogle

or

http://www.autobahnpower.com/p...tives

Or at your local napa or car quest...most checkers and autozones don't carry it

/\ I provided a website that is decently priced.

 

Thank you very much!! I appreciate all the help. I will post with some results...

 

Do you get free retests in CA?

In colorado they will test and if you fail you get 2 free retests withing 30 days

 

Unfortunatley i dont think so. I had to go to a test only station, so i am pretty sure i will have to pay for another test. I will probably try and just pay for a pre test and see how that works out... Probably save me like $30...

 

Well GL ....and most of that if not all is a DIY job

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by duanem &raquo;</TD></TR><TR><TD CLASS="quote">Here are the other readings:

15 MPH:

co2 14.3
o2 0.0
HC 117
co .72
no 52

25 MPH: this is where i had problems

co2 10.9
o2 4.1
HC 1788** max was 93
co 1.60** max was .63
no 584

so what do you guys think???</TD></TR></TABLE>

by the readings looks like you're running lean, I would do a check or have someone check out your O2 signal with a labscope not a DVOM.

 

I just went through this with my '90 EX. Turned out an O2 sensor had failed, causing too much unburned fuel to flow through the CAT thereby ruining it, so it cost me $450 to get my car through smog. I don't think mine failed on HC, so don't go by my experience. Just keep in mind, your car has a lot of miles and stuff does eventally wear out or go bad.

My personal lesson: O2 sensors are cheap enough they ought to be replaced every 100K or so. Don't wait until they wipe our your CAT