Emissions tricks..

[JOEDEZZY]

What are some tips and tricks to help pass emissions? Personally I'm failing on my hydrocarbons (un-burnt fuel) like I'm missing or I have a bad valve or something, but if you have any tricks post em up, they might be benificial to somebody else.

 

[ak bandit]

My buddy had problems passing emissions. He just whipped out a screwdriver and started adjusting his mixture right there. He said his truck sounded like crap, but they gave him a sticker. He re-adjusted it back after he left the shop.

 

[GEORGIA GABE]

create a vacuum leak and then go retest it.
gabe

 

[CustomChevy]

What are some tips and tricks to help pass emissions? Personally I'm failing on my hydrocarbons (un-burnt fuel) like I'm missing or I have a bad valve or something, but if you have any tricks post em up, they might be benificial to somebody else.

friend of mine who used to do E-tests up here in canada alsways told me

if you're failing HCO's to run the test at as slow of an RPM as you can, and with the engine as cold as possible.

 

[DirtyJim]

$$$$ always works

 

[Avery4jc]

What truck, year?

I failed terribly w/ my 85 because the computer wasn't hooked up for emissions, we hooked it up and tuned it in and it passed.

-Avery

 

[JOEDEZZY]

$$$$ always works

I will accept any money or parts that people are willing to donate to my cause

 

[Janitorjim8]

if you're failing HCO's to run the test at as slow of an RPM as you can, and with the engine as cold as possible.[/quote]

I always thought the hotter you got the cats the better they worked?

 

[barneybasher1010]

Put on a new cat. converter it will burn all gases.It worked for me before.

 

[JOEDEZZY]

I've got a 77, so theres no computer and and I'm not running a Cat either

 

[1987Chevy]

Cut your gas with alcohol the more you add the lower the emissions.

 

[GEORGIA GABE]

Ill restate it one more time.... If it has too high HC then try creating a vaccuum leak, this will cause the mixture to lean out... It is not a permanent solution, you will have to have someone rebuild the carb most likely for that. If it is running really rich, then you should smell it in the exhaust. if you create a vaccuum leak and then smell it again after about 5 min of driving and it is better, then go retest it.

Or take it to a repair shop where they know how to work on carbs
gabe
cmon down to ga and Ill fix it
www.jandlautoservice.com

of course this is what a catalitic converter is designed to do so if that does not work then its cat time.

 

[JOEDEZZY]

couldnt i just lean it out before I went in to get it tested by adjusting the a/f mixture? like coming out 3 to3 1/2 turns on the a/f mixture screw. kinda off the subject, but when adjusting your carb, how many turns should you come out on your a/f adjustment? I've been told once you get it down to when the engine is studering you come out 1 1/2 turns and I've also been told 2 1/2 turns (where its at now). I know this isnt an exact way of adjusting your carb but whats a good rule of thumb? oh and also I'm in Tucson so i think I'm like 2000 feet above sea level.

 

[fatbob]

Hook up a tach and turn in the mixture screw untill you see a drop in RPM. Then turn it back to just before where it dropped, maybe a 1/4 turn at most. This is the lean drop method. If you get it TOO lean, you will get a miss, and some cylinders will not burn the fuel. This will cause you to have high hydrocarbons (un-burnt fuel).
Another trick I learned when I passed the sniffer, but failed when they noticed the breather hose was unhooked from the air filter. I just hooked it up , then I failed the sniffer. So you might just plug that hose up with a rag, and hook both ends back up so it will pass the visual inspection. This will help you to keep from failing do to excessive blowby.

 

[GEORGIA GABE]

ok, those little screws are just for idle. Anything off idle will be controled by whats going on inside your carb..there are NO external adjustments for this.
gabe

 

[JOEDEZZY]

ok, those little screws are just for idle. Anything off idle will be controled by whats going on inside your carb..there are NO external adjustments for this.
gabe

what? really? I agree that the screw on the side where your throttle linkage is, is for idle adjustment, but arent the 2 screws in the front are for you a/f ratio adjustment. I mean I'm not an expert by any means, but it just doesnt seem logical not to have an adjustment outside the carb.

 

[hack500]

depending on the carb there may be: metering spring; primary jets; power valves; secondary jets; step-up springs; booster pumps; p.o.e. springs... just whole bunch of stuff that's all internal.

 

[JOEDEZZY]

yeah ok that makes sense, different carbs different adjustments, I am starting to think my problem actually is my carb. Heres the story, I bought this Blazer with a blown engine and just last week put a 350 in it, I used the same carb from the blown engine, thinking it was a 350, I just looked up the numbers from the blown block and its actually a 267 (never even heard of it before now) So if the carb I used has the minimum cfm's for that size block then I'm actually running a 500 cfm carb when I should be running a 650.