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emission test...fuel mixture off the charts. failed twice,84 720 z24.


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hey guys ,I am back. need your help again.. they started the emission program again here in Colorado 2 years ago.. 2 years ago I passed on the first try  through...since then I have only put 6000 miles on the truck...so I changed the oil, and new air filter..new gas cap..and took it in...it failed badly on CO MIXTURE...OVER DOUBLE THE limit.   the limit was 55.0000... and I was at like   114.0000.... so I came home in defeat...so I changed the plugs on drivers side,  and leaned the idle fuel mix super lean.... I also advanced the timing just a little{did it last time}....took it back through....boom ..104.0000 on CO. NOT even close....so this is a brand new facility, and they have a full diagnostic center, so I had them run a full diagnostic on it....For one thing.. I had this device I made holding the choke flap open , because my choke quit working a while ago.   so it was blocking some air flow....second,,, he said to check the high altitude compensator...must be functioning,  I think I capped off a line from that thing a long time ago....  also,   he said the booster venture was loose and rattling ..I don't know what that is..... also the big valve on the inlet tube of the air filter needs to be open when its warm.....so, I guess where I am at right now is, fix the choke. I think that has a lot to do with it..and get all the hoses hooked up to the carb... I mean, the only thing different from 2 years ago is the deal I made to hold the choke open...6000 miles ago.....I have had the truck 30 years now, and I am not going to give up on it..    oh yea,  the plugs were pretty black when I pulled them......so , lets start with the choke first...what is the plan to get it fixed....        84   Datsun   720   z24   4x4

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ok guys, whats up, I need help...I got the choke to stay open on its own....the manual said to blow air through inlet and out let holes on the high altitude compensator.  does that mean in and out of top three holes, or from bottom line to top line..no air passes through the top three... also, I am looking at thermal vacuum valve, and vacuum control valve as possibilities.....gotta have the truck back together tomorrow..gonna snow.....

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