Fuel Mix/ idling issues...

[cv70chall]

Hi everyone! Hope we've all recovered from our turkey comas.
I've noticed over the last couple of weeks that my exhaust smelled a bit rich. A few days ago, after filling the tank, the engine sputtered and died at the light- and it took a couple of minutes and attempts to start it before it cranked back up and seemed to run normally- until I slowed to pull up the driveway and it nearly sputtered out again.
Does not seem like an idle issue, so what could it be? The car runs good, idles nice. I ordered a new set of plugs (the existing plugs are a bit over 2 years old- but I've maybe put 500-600 miles on the care in that time, so not sure if it's the culprit, but they'll get replaced anyway.
Can a slightly loose spark plug cable cause this? I'm asking as I felt that two or three wires seemed a little "loose".

Thoughts, anyone?

 

[Supersnake]

Is this a 440+6 engine? Need to know to be able to help you.

 

[cv70chall]

Is this a 440+6 engine? Need to know to be able to help you.

440RB with a 4bbl Holley Avenger 670

 

[Chryco Psycho]

Could have a gasket leak inside the carb or just need tuning correctly , or possibly you have more ethanol in the gas that you bought recently .
I would suggest tuning it .
Not sure why you are running such a small carb on a 440 , I typically use 700-750 on 340s

 

[Xcudame]

It's Fall/Winter, and you need to tune it accordingly. You need to drive your car more!!

 

[fasjac]

Agree with all. Read those plugs when you replace, they tell a story.

 

[rklein71]

Don’t rule out ignition. A weak spark can mimic carb issues.

 

[cv70chall]

Could have a gasket leak inside the carb or just need tuning correctly , or possibly you have more ethanol in the gas that you bought recently .
I would suggest tuning it .
Not sure why you are running such a small carb on a 440 , I typically use 700-750 on 340s

The carb was a knee-jerk mistake. Planning on a 700-750cfm in the Spring. Carb was tuned about 8 months ago.

 

[cv70chall]

Agree with all. Read those plugs when you replace, they tell a story.

Agreed.

 

[cuda joe]

bad wires will cause problems running lean you will get a missfire smells really bad cheak the color of the spark should be blue