I'll try that.  The problem I have with spraying things to check for leaks is that the air intake is so close to that area (I have a K&N cone filter) that you can never tell whether the spray is going through a leak or just being sucked through the normal route. 

To check for a vacuum leak, use a propane torch. Do not light the torch. The engine vacuum will suck the propane into any leak and you'll hear the running engine increase in speed. Move the turned on torch around the intake and all the hoses and look and listen if the idle increases.

Yes, I know it was your thread. I wasn"t directing my comments toward you, jwakil. I was providing the information to the other posters who were trying to help you with an incomplete explanation of the problem.

Vacuum leaks can also occur at the join between the intake manifold and the head. This happens most often when there is an aftermarket intake manifold and header and the mounting flanges are not the same thickness.

Kelley

You may have vacuum connections at the manifold as well, which could leak, in addition to the carb mount itself.

That was my thread .  The problem I had with that was it was kind of variable.  Not sure if the hole size was changing or what.  Starting was also a little harder and inconsistant.  I was also later told that the overflow should always be open.  I think I can try blocking the pipe again, but that is not a real fix in my mind.  I'm thinking now an air leak is a plausible cause.  Since at highway speeds, the problem gets worse, I think it's probably because there is more air flow in the engine bay at those speeds.  However, the only place I can think of an air leak would be where the carb attaches to the intake.  One of the screws was hard to reach and tighten, so if that is loose, I might be getting some air in there. 

Check out the thread "Engine stuttering under load again". The engine wasn't running until he plugged the fuel overflow and put a small hole in the plug to get the engine to run.

Kelley

If it was a Honda 50 or a lawn mower - I'm 99% sure that something is stuck in the main jet. Something can float up and jamb only to fall out later to rejam up in there. I'd be taking the carb out to REALLY clean it. If it runs OK sometimes and sometimes not - crap in the float bowl... IMHNMRO (in my humble non mini related opinion....)

I've thought about the richer needle, however, there have been times in the past that the car ran fine.  I figure a needle would be the issue only if it had always run crappy.

Well the jet is new, and I had the similar problems with the old one, so I doubt it's that.  One think I was wondering about, if the fuel float level is not set right, could it cause my symptions?

You need a richer needle. What's in it now and what's your engine spec?

I had the same problem for months and it turned out to be a little chunk of something that was stuck in the jet.  Doug, who is here on the board, told me that this is a common problem with HIF carbs.  I took the jet off, sprayed carb cleaner and compressed air through it, and lived happily ever after. 

Start with the easy stuff first. Look for air leaks around the carb and manifold and make sure the breather intake tube on the carb is hooked up or plugged.

Almost identical situation I had two years ago.

Pull the carb and send it off to Joe Curto, NY.  He found that with mine there was worn parts and a boched hacked internal repair.  He straigtened it out, I sent my specs on my motor and he picked a BDL needle, installed it, threw in a couple more needles and said good luck.

I bolted it in and all those troubles went away - like magic.  

Just to cover all your bases, check all your ground straps and ensure no corrosion and good connections.

After much trouble shooting, including replacing my fuel pump, I've found that I'm still running lean with my HIF44 carb.  I have the mixture screw all the way rich, I still get occasional slight stuttering on local streets when I'm under load in 3rd or 4th gear, but now I also lose power when I'm at cruising speeds on the freeway (feels like the car is running out of gas or something).  I've learned that if I pull the choke, the problem goes away.  Anyone have any suggestions of what in the carb, or the engine in general could be causing me to be unable to richen the mixture other than by choke?