340 not running good need help

[Cardinge72]

I have a 340 with issues idling and a bog when the car is under acceleration and it also seems to surge

 

[toolmanmike]

When did it start?

 

[jerry6]

What year , carburetor ? Did it just start ?

 

[servicegroup]

Hi,
Perhaps if you could provide us a little more info on the issue. Certain idles/loads/speeds. Is it backfiring?

As you guessed this could be a number of things. My 318 did this a while back and it turned out to be a single bad plug.

Could be a number of things,

Check the obvious things first. Plugs , Wires, Distributor (check for moisture), check timing and vacuum. Then move to fuel delivery accel pump, carb and intake for leaks.

 

[VonCramp]

How long had it been since you last drove the car? The ethanol in your carb could've done some damage if it had been sitting a while.

 

[66340SEDAN]

How long had it been since you last drove the car? The ethanol in your carb could've done some damage if it had been sitting a while.

This^^^^^carb probably needs a complete rebuild

 

[Cardinge72]

My apologies this is new to me it stalls when the engine is warm at a idle example at a light and it also does the surging at Around 60 mph. When I floor it it also bogs it's equipped with a edlebrock carb, stock intakealso what should the timing be set to it's a 1972 340 4bbl.