hello, my brother n law has a 69 mustang, tried to pass emissions yesterday and said that his air to fuel mixture is to rich, what should he do

 

Not all of the fuel is being burned completely since it is rich and it has high carbon monoxide emissions. You need to lean it out a little. (but i cant tell u how, idk)

 

Tune the carburetor.

Adjust the mixture by turning the two screws mounted in the front of the throttle plate...

 

I'm guna send this post to the "classics" section. Those dudes really know their stuff.

It should be a pretty simple adjustment. What carb do you have on it?

 

um...no...not really..no..[sm=joke.gif]
If you don't know how to adjust a carb, I would stop by a shop and tell one of the guys, you'll buy him a six pack if he leans er out for ya.

 

Lean her out by adjusting the screws to the counter-clockwise about a 1/4 screw turn. See if that leans it out enough to pass inspection. You just need more air in the mixture. You may also have a leak in your exhaust system. Check that out.