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-   -   aircare thread (https://www.revscene.net/forums/227049-aircare-thread.html)

originalhypa 08-10-2004 02:03 PM

aircare thread
 
Okay, since some of you have been asking for it, and I just failed :flamemad:, let's go through what causes high HC, CO2, and NoX. I know I'm not terribly familiar with what to do if you have high readings.

So here goes, post up what you know as far as HC, CO2, and NoX goes, and I'll put it all in an info thread which I can sticky.

let's make this happen.
:)

originalhypa 08-10-2004 02:04 PM

Possible Causes of High Hydrocarbon (HC) Emissions


Hydrocarbons relate to unburned fuel. You may logically think that must mean that the engine is getting too much fuel. However, that is only one of many possibilities ranging from fuel problems, to electrical problems, to internal engine problems such as piston rings that can cause HC emissions to be excessive.

In order to pinpoint the cause of excessive HC emissions, the following systems (if applicable) will need to be checked, usually in the order shown below:

Lean or Rich Air-Fuel Ratio
For an engine to operate as designed, the correct ratio of fuel to air must be delivered to the cylinders. If the fuel system is delivering a leaner than ideal air-fuel ratio, it may result in lean misfire and cause high hydrocarbons. If the fuel system is too rich, it also may result in high HC but will be accompanied by high CO as well.

For more info regarding the diagnosis of fuel delivery systems, see Fuel System Testing

Inadequate Catalytic Converter Efficiency
For vehicles that are 1988 model year or newer, it is very important that the catalytic converter be operating at 90% efficiency or better. That means that the emissions that come out of the tailpipe must be no more than 10% of what goes in.

For more info regarding how to determine catalytic converter efficiency, see Catalytic Converter Testing

Induction System Problems
There are many aspects of the engine's air induction system (hoses, intake runners, intake manifold, vacuum-controlled devices) that can cause disruption in the air and fuel getting to the cylinders and result in high HC. Incorrect PCV valve/orifice flow rate can also cause similar symptoms. Leaking EGR valves also may cause excessive HC emissions.

For more info regarding how induction system problems are identified, see Induction System Testing

Poor Ignition Performance
Ignition defects including dirty spark plugs, leaking or open-circuited spark plugs or wires, or defective ignition coils can all result in a shortage of spark energy. Any shortage of spark energy may cause high HC emissions.

If the spark occurs at the wrong time, incomplete combustion and high hydrocarbons may result. Too much spark advance could be due to an incorrect adjustment or a defect in mechanical or vacuum advance mechanisms.

For more info on testing ignition systems for inadequate spark energy or incorrect spark timing, see Ignition System Testing

Uneven Output Among the Engine's Cylinders
At this stage of the diagnosis the technician should be sure that the air-fuel ratio is correct, there are no external vacuum leaks, and the ignition system is operating normally. There are still many possible causes of high hydrocarbons, most of which are either internal engine problems or tough-to-detect induction system problems such as valve deposits or a leaking EGR valve. On fuel-injected vehicles, poor fuel atomization is a common cause of HC problems.

For all of these remaining possibilities, checking for uneven power output amongst cylinders will usually help to track down the cause of the problem.

originalhypa 08-10-2004 02:13 PM

Possible Causes of High Carbon Monoxide (CO) Emissions


High CO means too much fuel. Fuel can only come from three sources: the crankcase vapor control system, the evaporative control system, or the actual fuel delivery system.

The fuel delivery system is certainly the most likely culprit but in most cases it is very quick and easy to eliminate the other two possibilities first. However, if it is problematic to check the evaporative system purging, it is probably wise to go straight to fuel delivery system diagnosis.

In order to pinpoint the cause of excessive CO emissions, the following systems and possible defects will need to be checked, usually (but not always) in this order:

Excessive Crankcase Blowby or PCV Flow
If oil vapours in the engine's crankcase are excessive, or the oil is dirty or contaminated, excessive CO emissions can result. Dirty or contaminated oil is easily rectified by an oil change. Excess crankcase vapour flow can be caused by an incorrect PCV valve or by serious internal engine damage such as worn-out piston rings. Serious internal engine damage can only be remedied by major engine repair or overhaul.

For more info regarding the diagnosis of crankcase vapour control systems, see Crankcase Vapour Control System Testing.

Saturated Evaporative Control System
The charcoal canister stores fuel system vapors until they can be withdrawn and burned in the engine. Under normal circumstances, this should never result in excessive CO for more than a few seconds. It is possible for charcoal canisters to become saturated with fuel. This essentially means that they can never be cleared of HC vapors and need to be replaced.

For more info on how testing for excessive crankcase blow-by gases, see Evaporative Control System Testing.

Rich Air-Fuel Mixture
There are many aspects of the engine's fuel delivery system that may need to be checked when diagnosing a rich air/fuel mixture. That is the main reason that this is listed behind crankcase vapor and evaporative emission control systems-even though they are less likely causes of the problem, they are much easier and quicker to check.

When diagnosing a rich air-fuel mixture, it is important to keep in mind the possibility of a defect in an entirely different area affecting the operation of the fuel delivery system. For example, certain mechanical engine defects may cause abnormally low engine vacuum and result in the fuel system delivering more fuel than is actually needed by the engine. The symptom of excess CO may lead one to think that the defect lies with the fuel system but the problem actually lies elsewhere.

For detailed info regarding the diagnosis of fuel delivery systems, see Fuel System Testing.

Are Other Problems Being Masked?
An additional consideration if your vehicle failed with very high CO emissions is the possibility that it may also have a NOx problem that was masked by the high CO. Sometimes restoring the air/fuel ratio to the proper range uncovers a NOx problem. The NOx defect may have existed previously but wasn't evident because of the lack of oxygen that accompanies a rich mixture.

If possible, the technician should perform a quick check of NOx control systems after identifying the cause of the CO problem. Any problems found should be included in the total repair estimate. However, in these circumstances any NOx related repairs would be a lower priority than the CO related repairs.

At any rate, you should be aware that it is possible that a NOx problem may become evident after a CO problem is repaired.

originalhypa 08-10-2004 02:14 PM

Possible Causes of High Oxides of Nitrogen (NOx) Emissions


In order to pinpoint the cause of excessive NOx emissions, the following systems (if applicable) and possible defects will need to be checked, usually in this order:

Over-Advanced Ignition Timing
Older vehicles have ignition timing systems that are adjustable and, unfortunately, anything that is adjustable is also mal-adjustable.

Fortunately, ignition timing is usually quick and easy to check. For more details, see Ignition System Testing.

Inadequate Exhaust Gas Recirculation (EGR) Flow
Operation of the Exhaust Gas Recirculation (EGR) system should be checked completely. To do this there are three areas that the technician must check:

the EGR valve
the EGR exhaust passage(s)
the EGR control system
For more information on these procedures see Exhaust Gas Recirculation (EGR) System Testing.

Lean Air-Fuel Ratio
The technician should check to ensure that there is not an excessively lean mixture being burned. Depending on the vehicle, its fuel system, and its emissions control systems, this may involve simply looking at the VIR, measuring engine-out emission levels, and O2 sensor testing.

For detailed info regarding the diagnosis of fuel delivery systems, see Fuel System Testing.

Defective Three-Way Catalytic Converter
Your technician should test the catalyst by performing a converter efficiency test (see Catalytic Converter Testing). Note that this only applies if the vehicle is equipped with a three-way catalytic converter (some 1980-87 vehicles and all 1988 and newer vehicles have three-way catalytic converters).

Combustion Chamber Deposits
If the above possibilities have been conclusively checked and no problems found, it is reasonable to conclude that combustion chamber deposits are contributing to excessive NOx emissions. For additional information see Combustion Chamber Deposits.

fliptuner 11-22-2004 04:30 PM

Just want to a a tid bit of info about NOx

It's ALWAYS related to high EGT - regardless of if it's caused by timing, lean mixture, stuck EGR or yes, even from an hot running engine cause by some mechanical failure (ie blown HG, bad water pump, low coolant, thermal sw. not turning fan on, etc)

Overseas Auto1 07-07-2006 01:59 PM

You know what? If your car was made in 2003 or later, it will never have to go to aircare. Aircare will wind up in 2011

Lex_GTX 03-17-2007 12:05 AM

On older cars that fail due to high HCs, retard your timing as much as you can before going through.

bomexintegra02 04-10-2007 07:51 PM

is that true about air care not need if 03 or newer?

turner492 09-10-2007 01:32 PM

i gotta love living in a town that has no air care rules :D haha

GcyK 09-17-2007 04:38 PM

i heard that theres no more air care after 2010

cccatch 03-24-2008 11:54 AM

rip aircare?
 
Quote:

Originally Posted by GcyK (Post 5446065)
i heard that theres no more air care after 2010

is this a fact? please confirm :haha:

Shogun 04-27-2008 02:47 PM

This is from the AIRCARE website
( http://www.aircare.ca/faqwindow.php?id=56 )


Q. Is the AirCare program ending?

A. The current testing contract with Envirotest Canada to provide light-duty vehicle emissions testing in this region runs until December 31, 2011. The Province has not made a decision on the future of light-duty vehicle emissions testing beyond 2011. In 2009 - 2010, the Province is scheduled to review the performance of AirCare and determine if automobile emissions remain a significant contributor to the air quality in this region and, if so, the most suitable program model for the future.

fukkeneh240 09-04-2008 09:47 AM

i read somewhere on the aircare website that they are getting new testing machines to start testing 2002 and newer cars. damn it. i have to find it again.

kookoobird88 01-15-2009 09:41 PM

ah i just failed aircare because of my HC
limit is 119 i had 292..

Psykopathik 07-27-2009 03:31 PM

got this off the AC site

Quote:

AirCare Review
Almost from the moment it was introduced in 1992, rumours have circulated about the imminent demise of the AirCare program. Now, with the approaching expiry of the current testing contract in 2011, AirCare staff have fielded numerous enquires from technicians, repair shop owners and the motoring public about the future of the program. Hopefully, this article will shed some light on the question.

First, it is important to note that only the contract with Envirotest Canada to provide emissions testing services is set to expire on December 31, 2011. The testing contract and the requirement for emissions testing are two separate matters. December 31, 2011 only ends the testing contract, the BC Motor Vehicle Act Regulation that requires vehicle emissions testing can only be repealed by the BC Legislature.


bcrdukes 07-27-2009 05:09 PM

NOOOOOOOOOOOOOOOOOOO!!!!!! FUCK YOU AIRCARE!

JDM300ZXTT 08-13-2009 09:58 PM

Aircare is a waste of time. Cops should be able to give tickets to big stinky over rich black smoke spewing diesel trucks and buses, however.

c32 12-11-2009 06:26 PM

hey guys i wanna go see if im running to rich or lean, do i just drive into the air care place behind mercedes benz on boundry and ask them to do that? does anyone know how much they charge? im seeing alot of whiteish smoke come out of exhaust everytime i stop at a red light and i dunno if its normal or not.. i never see any other cars pouring out exhaust smoke like mine though

c32 12-11-2009 06:28 PM

also how can i check if my car is aircared and till when and if i get it checked do i get charged $$$

dbau_dc4 01-25-2010 10:48 AM

i keep failing on oxides of nitrogen
i just changed o2 sensor and it did go down by 100
max is 1215 and i got 1265

i have a 1990 acura integra with a jdm b16a swap
can anyone suggest anything to do ?

jribchester8 12-13-2011 10:38 PM

c32 you can check with your insurance company. they will not charge you.

slick724 10-25-2012 10:02 AM

Before 1996 - Aircare expires every year
After 1996 - Aircare expires every 2 years

First Aircare needed on 7th year car

Aircare expiry date shows bottom right of insurance registration

Announced! - Aircare program to be scrapped Dec 31, 2014... still need aircare before until then....

CRXED9 10-28-2012 10:55 AM

Is aircare actually going to be scrapped? They keep saying it but it never happens. It generates a lot of income for the gov.

slick724 11-01-2012 08:03 AM

yea it was announce on an icbc bulletin and in van sun

SpartanAir 11-01-2012 07:24 PM

Dammit...Mine is due this month, I have a Check Engine light on and was told it was an 02 sensor, but haven't had the funds to do it yet...

Does anyone know if they will let me take the test, or could possibly pass, with that light on? Car runs perfectly fine while it's on, has been for a few months..


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