if it was close i wouldnt be posting this but how did this happen any theorys?

 

 

Running pig rich at low idle. Sounds like leaking fuel injectors. Check the fuel pressure and keep the gauge attached then kill the engine and note how quickly the fuel pressure drops. If the pressure doesn't hold for at least 20 seconds your injectors may be leaking.

It passed on high idle so maybe only one or two injectors are leaking.

Another possibility is when testing the low idle the o2 sensor doesn't heat up enough to function properly. To remedy this you may need to upgrade to a heated 3 or 4 wire 02 sensor. The o2 sensor relies on exhaust gasses to keep it hot and working at all times, but low idle means less heat, period.

 

being carbureted i dont think i have fuel injectors and an o2 sensor? i guess i dont have to upgrade i just have to get one period =P

 

i might get my timing done and tune my carb? i figure that would kill me but why only low idle D= i expected to fail with flying colors on both

 

Excellent fail on my part...sorry...too funny.

It is still running pig rich at idle. Look down the throat of the carb, try to see if any fuel is dripping down onto the throttle blades. If it is dripping I would rebuild the carb (probably a needle and seat).

At high idle the engine has a better chance of burning off any extra fuel and the catalytic converter is hotter so it works better.

 

i would say you have a lean misfire, the low CO reading along with the high O2 tells me that.
HC is unburned fuel and to be rich enough to cause rich misfire, CO would be thru the roof. CO2 is also low.
a good hot cat will hit 5 or better on CO2 while cranking the motor with the ignition disabled.

when i was repairing cars for a living, when something like that came into the shop, the first thing i would look for is vacuum leaks.
a good strong carb cleaner can help get you in the general area.
possible loose throttle shaft, but it would have to be really loose.
to adjust the idle mixture screws, turn them for best idle and highest vacuum, then turn both in till the idle just starts to get a little rough.
the EGR valve could be leaking a little bit. it doesn't take much EGR at idle to cause a miss.
weak cylinders can cause misfire at low speed.
so a standard and a running compression test would be in order.

 

thanks denn sha well i know i have vaccum leaks and i know my egr cant be leaking because its not there carb should be fine cause its brand new but needs to be adjusted i suppose but before i adjust my carb i should find and fix all my vaccum leaks my entire smog system was yanked out (the previous owner) and theres alot of open hoses and whatever it is coming of the stock manifold on both sides its open and one one side it looks like they took once again bolt cutters to it D= they took my a/c out the same way