I'm wondering where I should begin....My car starts fine and runs fairly smooth, but it seems to idle rougher the longer I drive it. I've run a bottle of carb cleaner thru it. I was going to try spark plugs next. Any thoughts?

thanks again.

 

Way to many things it could be, My first thought was the automatic choke not set correct.

 

My first thought was the same as Ratfink, if it runs fine for startup when the choke is partly/mostly closed and then doesn't run as well once warmed up the choke may be stuck or misadjusted and is not opening fully causing a rich condition. Take a look at the choke flap before you start it, a minute after you start it, then drive 15 min. and look at it again. When it's warmed up it should be vertical or fully open.
Jon

 

How long has the problem been going on? Any carb or engine work done on it around the time you started having problems?

 

If as stated above, the choke is wide open when the car is warmed, take a look at the plugs. Pull a spark plug and see what condition it's in.

If it looks like this:



That a good thing.

If it looks like this:

The carb is running too rich.

My car was running rough like yours. Rebuilt the carb and put electronic ignition and that really helped things.

Check vacuum hoses for leaks and...ah heck...I think it's called a PCV valve that goes from the carb to valve cover. That could also make the car run rough.

 

deleted

 

It has been going on since I bought the car in early March. Some days seemed worse than others. I have not had any engine work done yet. I have not driven it much while doing other work and it is currently at the shop getting some rust cut out. I should be getting it back this week and will check the plugs and choke.

 

as above, my first thought would go to the choke as well

when cold the choke should be closed, when warm it should be wide open.
if that's the case then what provbably happens is that the car is running way too lean.
the choke will adjust (overrich setting) to compensate, but once warm you're not getting enough fuel.

So check on the choke first if it's closed cold and warm open (make sure you floor the pedal once before you start it up cold)
if that's ok check the spark plugs and post a pic

 

Finally got the car back from the body shop (getting some rust in the wheel wells cleaned out) and pulled one of the plugs. Looks like the first picture posted above. While the choke is not closed, it is not fully vertical either when warmed up. So I assume I need the choke adjusted.

 

Sounds like a good start.