Failed emissions
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Joined: Apr 2004
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Your HC problem is a rich idle. Make sure you idle adjustments are a bit on the lean side, your float level is correct, choke is not closed, and power valve not blown. Also, clean oil will help that as well. Make sure the PCV is working.
CO is usually take care of by the cat, even when you are a bit rich. If you clean up the rich idle, you may pass on CO.
Your profile says '71 F100 ....is that right? You would not have a cat in that case, so please, give us as many specifics as possible.
CO is usually take care of by the cat, even when you are a bit rich. If you clean up the rich idle, you may pass on CO.
Your profile says '71 F100 ....is that right? You would not have a cat in that case, so please, give us as many specifics as possible.
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New User
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specifics
Its a 302 out of a Bronco, not sure what year. It has a Holley 2barrel carb. Fresh oil, plugs & wires, gaskets, etc etc. It has a 3 speed tranny & its a 3 on the tree. Trying to take it to Texas from Arizona in next couple days for real highway test, but held up by failed emissions now, arghh!
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302 out of a Bronco...in what, your '71? What standards are you being tested to? Do you have cats? Are you being test to the standards for a cat equipped vehicle but don't have them?? Is there a sticker on the valve cover of the engine? What size Holley 2bbl?
Lead Driver
Joined: Aug 2003
Posts: 7,592
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From: **** hole San Jose ca.
Did you do a tune up before and adjust the carb air/fuel mixtures screws out about 1/2 turn letting it having a little more air plus run some higher octane gas. "Helps"
orich
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Laughing Gas
Joined: Mar 2013
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From: Garner NC
If I had a dime for every rich running Holley I'd be a bazillionaire. It is the most abused after market item I can think of. Start with the basics here or you will chase your tail forever. Be sure:
1. The carb is correctly sized. Is it a 350cfm? A 500 is way too big for a 302.
2. The jets are properly sized and the correct spring set installed. Determined during tuning.
3. Find a local expert to lend a hand in tuning it up if *you* are not an expert. And I'm not digging on you here. Holley's are about the details and are definitely not 'bolt and go.' I have a drag racing friend I regularly use to fix an 'enthusiast' install. The outcome is amazing. I am not a Holley expert though I know a lot about Autolites and how to get them to behave, but I would not hesitate to enlist someone in the know for a Holley setup. And better if they compete a quarter mile at a time. There's many an 'expert because I own one' out there.
Good luck Brother.
1. The carb is correctly sized. Is it a 350cfm? A 500 is way too big for a 302.
2. The jets are properly sized and the correct spring set installed. Determined during tuning.
3. Find a local expert to lend a hand in tuning it up if *you* are not an expert. And I'm not digging on you here. Holley's are about the details and are definitely not 'bolt and go.' I have a drag racing friend I regularly use to fix an 'enthusiast' install. The outcome is amazing. I am not a Holley expert though I know a lot about Autolites and how to get them to behave, but I would not hesitate to enlist someone in the know for a Holley setup. And better if they compete a quarter mile at a time. There's many an 'expert because I own one' out there.
Good luck Brother.
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In AZ, the law is vehicles back to 1967 (can you believe that???) have to be emissions tested but only in the Phoenix and Tucson area and the suburbs. This stupid law was passed in 1989, the year before I left there and it still stands.
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