running rough - sputtering

[CaribbeanBronco]

A few days ago the bronco starting running rough (not idleing or running smooth). I put some carburetor cleaner in the fuel and now it won't idle at all. I have to continually give it gas and even then it barely runs. I checked vaccum lines, looks good. Checked the fuel filter, seems good.
Any thoughts??

 

[caribbeanlivin]

Being down ther I doubt it's been sitting up for awhile. Holley carbs need to be cleaned after being sat up for a long time.

 

[gi_phil]

Do you have points in your distributor? If yes check the gap. Also does it backfire when reved up around 2500-3000 rpm? if yes then it could br somehting with the ignition. I would check the all of the basic things like the timming, coil, and points, if the carb has not acted up before this point.

 

[broncnaz]

Sounds like it might be flooding out on you check the float level. Might be a good time to rebuild. Any carb that sits for awhile can have this issue its not limited to holley's

 

[rsharpnm]

Could be bad fuel, too - esp. given the change in performance when you put additive in the fuel.

Get one of those water bottles from the store that has the nipple on it (Like Arrowhead or something). Get all the water out of it - blow it dry with a compressor. Put in a bit of gas, hook up a hose from the carb inlet to the bottle and hold it up over the carb while somebody cranks. Gravity will feed fuel into the carb -- which will have bad fuel in it for a while until the bowl clears. If it starts running better after a few seconds (when gas starts draining from the bottle), you've got bad fuel.

If it still runs like crap, check ignition. Points suck, so PLEASE don't say you're not still running those! LOL! If so, check gap and condition.

Good luck!