Failed Az emissions, Help

[bohntr28]

I just ran my 1971 Bronco with a 302 through the emissions test and failed. I have a Holley 670 TA carb and a RPM performer intake. I am running at 12 degs of timing. I do not know much about Holley's and don't really know a good mechanic out here in East Mesa nor do I want to pay someone to work on my rig. I was hoping you guys could help me out. Here is what it ran on the test:

HC loaded 288 with a standard of 450 (pass) HC idle 697 with a standard of 450 (fail)
CO loaded 7.47 with standard of 3.75 (fail) CO idle 10.37 with a standard of 5.0 (fail)

I looks like I am running rich to me. I just want to squeak it through as I've just come across a 90 5.0 mustang that I am going to swap in this summer. Any words of wisdom on this one. What sucks is that I live about 1/4 mile from Pinal county which would exempt me from emissions. Thanks for your help in advance. Dave

 

[broncnaz]

Turn the timing back to stock or less it will run like crap but should pass also I'd consider finding a smaller carb that 670 may be part of the running rich problem if you have any buddies with a 600 cfm or less carb try to borrow it for the test. I'd consider moving that 1/4 mile also I hate emissions

 

[bohntr28]

What is the stock timing supposed to be at? They don't list it in my Haynes manual.

 

[Bitch'nBronco]

Arent cars over 20 years old exempt from emissions in AZ? It is here, and I am hoping it is there too, cuz I am moving there. That could put a damper on my party.

 

[broncnaz]

Stock timing is 6 degrees. Emissions are required for all 68 and newer vehicles only in phoenix and tucson metro areas if you live elsewhere in the state you are exempt.

 

[COBlu77]

You need to turn your idle mixture screws clockwise to lean it out. Turn each a 1/4 turn at a time until it tries to die and then back out 1/4 turn each. You can put it back to normal after the E test. Also, change your oil and get a new air filter. This used to work for me every year in CO when I was running a carb.

 

[bohntr28]

nope. 1967 and later have to pass the sniff test and a visual inspection is required on 71 and later for PCV valve. Then there are the Cat's... In Maricopa county if you have collector car insurance and the vehicle is more than 15 years old then they will exempt you for emissions. The problem with this is that I could not find a carrier that would allow me to take it off road.

 

[bohntr28]

coblu77,
The oil only has 230 mile on it but it is a couple months old. The whole rig has been rebuilt (with the exception of the body). Should I still change the oil? I will adjust the carb again tonight. Thanks

 

[matt69]

Arizona is in the process of exmepting vehicles, similar to California. Last year I failed in AZ on the idle side, so I just turned up the idle to about 1300rpm and crossed my fingers. It passed.

 

[bohntr28]

Broncnaz,
The nope was not directed at you. 67 or 68? You are probably right.

 

[broncnaz]

No problem I've been wrong before. only other problem with the collector car status is you cant drive more than 3000 miles a year.
While I currently live in Tucson my bronco is registered out of town so no emissions for me yes I'm technically breaking law (flame me goody to shoers that claim they never break the law) but I dont drive my bronco in tucson and its not even in the city but every once in a while.

 

[70_Steve]

HC loaded 288 with a standard of 450 (pass) HC idle 697 with a standard of 450 (fail)
CO loaded 7.47 with standard of 3.75 (fail) CO idle 10.37 with a standard of 5.0 (fail)

Typically, you get a high CO if the mixture is too rich. You get high HC if there's a misfire of some sort. The high HC at idle could be because of the very rich idle mixture causing a misfire. You have high CO both at idle and under a load. The idle mixture screws will only help at idle. You need to do something to bring down the the CO under a load.

Take the other's suggestions. The idle mixture screws need to be adjusted to bring the emmisions into line at idle. Personally, I would adjust the idle mixture properly, then screw in the mixture screws 1/4 turn. You want to avoid a rough idle. A rough idle is the engine misfiring, and it can misfire because it's too lean just as well as because it's too rich. A lean idle misfire will cause high HC, just like a bad sparkplug wire or some other cause of misfire.

Set the timing back to 6-8 degrees, for now. Check to see that your PCV valve isn't clogged. Change the oil and install, or just remove, the air cleaner. One other thing you might want to try, to lean out the mixture under load, is to drop the level in the float bowls. I dropped the level in the float bowl on my Carter/Edelbrock about 3/4", and noticed a difference in the way the plugs looked. Much whiter. Also, if you can find it, put a couple cans of Dry Gas or some type of alcohol in the tank.

 

[03COBRA]

Get a PO box in the county a 1/4 mile down the road and register it to that. All kidding aside that sucks man... I have the same year Bronco and I am exempt in WA state.. I also have collector plates on it, maybe that plays a factor in having to get it tested or not.

 

[needabronco]

My brother in law bought his 72 for 2500 because it simply couldn't pass emissions in peoria. I would go for the PO box idea, only problem is you need a good physical address to do it. A quick fix would be to 'sell' it to somebody that you trust that lives in the county until you get the efi going or it becomes exempt. good luck.

 

[Broncobowsher]

Lean the idle a bit, that should bring down the loaded part just a little as well. Maybe enough to pass. Pull 5° out of the timing should help clean up the HC. Those 2 adjustments hould be enough to get you through without anything else. When done, set the timing back where it runs good.

They have been cracking down on the PO boxes. I lived at my Aunts house for several years, if you know what I mean. That was mainly due to the quanity, not quality of vehicles I drove.

Maricopa, and Pima county are emissions. vehicles that frequently drive into these countys also are required to pass (but few bother to test). Some parts of other countys near Phoenix are also starting to require testing.

Testing is required on all emission equipped vehicles, passenger vehicles start in '67. That is what makes a '66 Bronco so desirable in Phoenix.

 

[airman]

Turn up your idle, lean out a bit as recommended and if you have a KN type filter try a paper one. The oil in a freshly cleaned filter can add to CO.

You may want to check your floats too. Do they even open the hood on 71? You may be able to block off the vacuum advance for the loaded.

If you need a mechanic I can recommend one on Southern and Extension. Don't know any Queen Creek or AJ guys.

 

[hillbilly delux]

i agree on the lean bit. turn screws clockwise until engine begins to choke then turn it back 1/4 or 1/2 turn until it smooths or keep it very lean for test . it will not idle very well though.

 

[AZMike]

When I had my 73, a bottle of 80% isopropyl alcohol from Walgreens in about 1/4 tank of gas and a vacuum gauge was all I needed to pass. Make sure you go to the test with a well warmed up engine. I could never make that Q-jet pass without the alcohol. It would run like total crap for the test, but it would pass.

 

[COBlu77]

coblu77,
The oil only has 230 mile on it but it is a couple months old. The whole rig has been rebuilt (with the exception of the body). Should I still change the oil? I will adjust the carb again tonight. Thanks

If your oil only has 230 mi, don't worry about that. If leaning out the idle with the idle mixture screws doesn't work, then there are obviously other issues. I'd start with re-jetting the carb and looking at ignition (points, rotor, plugs, wires and timing). New PCV valve is a good call. All of which are relatively simple, but if you've never done it before you might want some help.

When I had a carb, after experimenting on my own without an exhaust analyzer, I took it to a good carb specialty shop and had them re-jet it using an exhaust analyzer. It is amazing what the proper mixture will do for you. After market carbs come with generic jetting and settings for sea level and street use. Getting them set up to your altitude, engine, and use is critical, but most just run them as they are.

All the government regulation BS aside, if you're failing the E test something is wrong and fixing the problem will make your Bronco run better and get better mileage. Since going to EFI (explaining that to the E test idiots is another story), I've never been even close to the limits and was told that my CO and HC readings are comparable to a new car.

 

[Dan's73]

I failed this year after squeaking by for the last 2, the only change made was replacing an Edelbrock Performer carb with the Holley TA 470. The timing was good, new oil change & plugs, everything else "normal". What I ended up having to do was up the idle speed a bit and jet it down from 57's to 55's; that got me through.

I don't recall what it was, but if you just try leaning the carb way down it'll mess with the other tested readings and you might still fail; I ran into this in '02,the first year I had my '73. I ended up taking it to a shop to have them get it through. I never got a straight answer as to what they did exactly, but they did say that it was too lean (from my adjustments) and the timing was "slightly off". In '03 all of the sniffer readings were good, but they failed me because there was a tiny hairline crack in the gas cap gasket. That pi**ed me off. Best of luck & let us know how it turns out.