Once again I've failed AirCare.

OK, I did everything right. Replaced the distributor cap and rotor, replaced the spark plugs, fresh oil and coolant, reduced fuel pressure 2psi (to 31) so that it drives & idles stoich, and lowered the idle down to 750 +/- 50rpm. Timing is stock at 15 degrees.

I took it for a burn before the test and got all the parts nice and hot. Waited about 20 mins in line, revving the engine and generally keeping everything hot.

Passed the gas cap test no problem.

During the driving test, the F*CKING IDIOT who was 'driving' my car on the rollers left it in 2nd gear during the 40km/h test. HELLO 3500rpm! It's called a short ratio transmission you pathetic excuse for a dungwad!! SHIFT TO THIRD!

It passed the driving test, regardless.

Then came the idle test. 40 seconds later the result, failed idle on both hydrocarbons and carbon monoxide, even though the O2 presence graph indicates it was idling stoich or thereabouts.

My question is this: Why would it fail these two so badly during idle when it aced the driving test so easily? As of now all I can think to do is turn the fuel pressure down about 10 psi and limp through. I don't think the cat's bad since I passed driving so easily. I don't think the O2's bad, just from watching the air/fuel gauge. What else could it be??

Here's the graphs & info:

 

What octane were you running.....sad to say but I would think it is your Cat.

 

92 and the cat is one year old. 2" High flow carsound. Maybe o2's???

 

What pressure is stock for your car? Also, since they don't care about NOX, advance the timing as much as spec allows if they check, that will bring HC down. Run lowest octane you can get.

 

i would try adjusting your idle up. try setting it to 1500.

 

Stock pressure is 32-38psi (it was tested at 31).

I can probably put the timing up 2 degrees, and 92's the lowest octane the car will run on without blowing up

serious, why would you put the idle up so high?


[Modified by raene, 1:28 PM 1/13/2003]

 

well stock b series timing is at 16degrees. So maybe you should advance it a little bit from 15 up to 17 or so.

EDITED because it actually isn't 14degrees like I previously stated but is actually 16degrees stock according to my chilton's manual.


[Modified by Blake K., 1:01 PM 1/14/2003]

 

if u wana pass just get coilovers and slam ur car then thell just waive u and u dont even have to take it cause they are scared it might hurt ur car

 

hi raene.. im from bc too
a friend has a 99 sir and has had problems with passing air care...
he tried some methyl hydrate from lordco and put it in his tank... he passed with flying colors.... its a cheat way but u can try that.

Anyways, try retarding your timing 1-2 degrees as well and check ur pcv valve

 

I have known people who have poured alcohol into the gas before emission testing...the alchohol is an oxygenator and helps reduce the emissions. Don't know how much they added, but I am guessing 10%-15% would not do anything harmfull - that is about the ratio of the crap that we have to run in CO during the winter.

Kirk

 

well, your driving test readings were both lower than the allowable for the idle test, so instead of trying to figure out what's going on, i'd simply adjust my idle to try and duplicate the driving test readings for my idle test as well.

 

friend had the same problem last week. he kept failing and he replaced the cat, o2, spark plugs, wires, cap and rotor and he was still failing the idle test. After a few hundred dollars later he found out his air filter was clogged up which caused him to fail on idle.

 

edited post...bump

 

Dear God you're right!

OK, idle's coming up... I'll go through in a couple of days... wish me luck

 

And dirty air filters are often times causes of high CO.
I would try some AC Delco X77a into the throttlebody/runners, let it sit, clean it out. That might help the HC go down. Advance the timing. Check the PCV valve, see if it's working and not stuck. And yes, try to adjust your idle, but FIND OUT THE ALLOWABLE LIMIT for an idle test. Here it is 1250 rpm. At 1251 rpm the counter will start over and you'll go nowhere on the test. Make sure the guy isn't using A/C on this test. And do an oil change with 20w50 before the test....

 

After I failed, I did some things for the second test and passed by a much better margin.

1) Make sure no fuel system cleaners are in the tank, they will increase emmisions.

2) Use the lowest octane gas your engine will tolerate. Lower octane fuel will burn more completely.

3) Advance timing to the upper limit, or as far as the engine will tolerate without knocking.

4) Get everything nice and hot before the test.

5) Add 2 bottles of HEET gas line drier to the tank before the test. I added them to about a half tank of gas.

This worked for me anyway.

Good luck.
G

 

I went back to Hell.

Failed again :D

Reason I'm happy? I dunno... noticeable decrease in emissions is always nice, plus I think I know what to do to get it to pass every time now. I think it's got a lean misfire at part throttle, which is causing higher CO readings and the NOx to increase gradually. So about four more pounds of fuel pressure (25 psi) should do 'er for a pass reading.

Notice how low the idle emissions are!

OK, the only real changes after all that waffling were that I checked all the vacuum tubes again, doublechecked the timing (it's stock), checked the intake air temp sensor for function, lowered the fuel pressure to 21 psi and raised the idle to about 1000. For some reason I can't get the idle higher than 1200 or so, and when it goes that high I get the idle bouncing up and down in time with the air/fuel gauge scrolling lean and rich, so I think my O2 is f*cked.

Anyway, here's the graphs:





On an amusing side note, I had the same guy drive my car this guy that drove it before. I had a large argument with him over his not shifting into 3rd and letting it sit at 3500rpm, which finally resulted in the supervisor coming over and telling me 'we do it because that's how it's done', which is complete and utter BS. That makes me feel better about screwing over the system in any possible way, since the AirCare system is utter BULLSHIT. Would they drive a 3-speed Mustang the same way they drive my 4.400 final-drive CRX? Then why do we both get put into 2nd gear? How about if I had the JDM ITR's 4.785 final-drive transmission? Would I still be in 2nd gear at 4500 rpm or whatever? Blehh :banghead:

OK, so I picked up some Guaranteed to Pass stuff, I'm going to use that tonight and go back tomorrow morning with fuel at 25 psi, no other changes. Any thoughts?

 

Make sure you run all of the "garanteed to pass" stuff out of your tank before you go back. That suff really agressivly cleans your engine and can cause you to fail if you still have it in your tank when you get tested again. Have you tried a diffrent O2 sensor yet? I dont know why your having so many problems. My brother has a CRX setup with no cat a supercharger and Dohc 1.6 and passes with flying colors. But I think where he lives (Houston) has less stringent emissions.

 

aren't you supposed to pour the guaranteed to pass then fill up the tank, and drive off half of the gas, with the guaranteed to pass still in the tank and go test it? thats what i did to my van, when it failed miserably, i poured in the guaranteed to pass, and voila passed with flying colors. it was an old chevy astro too. well, sure is nice having obd2 civic, cuz they didn't even do anything like what you have to do. just hooked up their computer to the plug, started it up and 5 seconds later got my reg. and tags. good luck and be sure to run the guaranteed to pass stuff. works wonders.