Failed Emissions

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Dec 19, 2003 | 03:15 PM

4X4BIGDOG

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Joined: Dec 2003

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From: UTAH

Failed Emissions

I took my 70 F100 in for Emissions testing and it failed the CO% test. Max is 4.50 and it reads 5.65. A little history on what I have done. Cleaned radiator, new wires, dist. cap, points, plugs. Rebuilt Carb. New air filter and PVC valve. Changed oil and filter. New exhsust tail pipe and muffler. All this was done before testing. Any ideas on what to check other than readjust carb and check timing? It has a 302/standard 4 speed/2110 carb. The choke seems to not be working correctly, hard as heck to start cold and won't idle when cold. Old gal has'nt been registered or ran since 96. Runs smooth when warm and I did warm her up good before taking her in. Any help is greatly appreciated.

Dec 19, 2003 | 06:21 PM

jor

Laughing Gas

Joined: Jan 2002

Posts: 1,008

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From: Tucson

Here's what I do every year to get my 67 352 to pass in Arizona:
* Timing at 5° BTDC (normally it's 8)
* Very lean fuel
* New PCV valve
* Add one gallon of denatured alcohol to 1/2 tank fuel ($9 per gal)
* Set the idle a couple of hundred above normal (maybe 875 or so)
I always feel as though I have gotten away with something when I pass and I usually celebrate with a cold beer. Good luck.
jor

Dec 19, 2003 | 09:21 PM

Faithful Old Road Dog

Elder User

Joined: May 2003

Posts: 520

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From: california

Wow! Here in California, a truck that old doesn't need to do the emission test. It was 73 and older vehicles exempt. I think it's now vehicles 30 years and older are exempt. I always thought that California was a pain when it came to emissions. I had a newer vehicle (79) that I needed to pass emissions. 2-3 blocks before I got to the smog station, I changed the metering rods in the Edelbrock carb to lean it out. After passing the test, I drove a few blocks away and changed the metering rods right back.

Dec 19, 2003 | 11:41 PM

4X4BIGDOG

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From: UTAH

Thanks guys. I have seen the one about the denatured alcohol a couple of times. Gonna give it a try. I readjusted the carb and reset the timing, was off pretty far. If I can just pass this one time, the old gal will be exempt from now on. And a cold one will be in order for sure.

Dec 20, 2003 | 01:24 AM

rainbowATF

Senior User

Joined: Oct 2003

Posts: 480

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From: Elyria, Ohio

Ohio E-check

For those Ohio counties with E-check. It is 25 years. There are exemptions for cars with $200 in emission repairs (owner labor doesn't count) and income exemptions. Bought 1979 F100 at end of October had to have e-check for only 8 weeks. Jan 1, 2004 no more emissions check. Passed with new air check valves and new cat and tuneup.

Dec 20, 2003 | 01:08 PM

ACESN8S

Elder User

Joined: Dec 2003

Posts: 534

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From: Hoquiam, WA

What's an emissions test?

Just kidding, I just haven't had to have one done for so many years....
Plus it also helps to live in a county where there are NO emission tests, or inspections.