Unexpected stalling !!! Where do i start????

[OUbesto]

Hi guys, been driving my '70 c-10, 402, AT this summer since completing a spring paint job, new interior etc and have had no issues driving 200+ total casual miles until yesterday! Was stopped at a traffic light waiting to turn left. Once traffic cleared and I knew I could get thru the intersection, I started to accelerate to make my turn and heard a "pop" (almost sound of a small backfire) and engine stalled. I put gear shift in neutral (since I was still drifting) but starter did not turn over or do anything! No cranking, no clicking...nada! Thank goodness an oncoming car saw me coming to a stop in the middle of the intersection and stopped or it would have been "T-bone time". I drifted through the turn and finally came to a complete stop. Put shifter in P, engine turned over and started right up...drove another 20-25 miles no unusual sounds, missing etc until about a mile from my house, then it did almost stalled after the "pop" but this time it did not die. then ran fine for final mile home.

Within last month:
- new plugs
- set timing
- new intake manifold
- oil change
- coolant flush
- new fuel filter
- fresh gas about 2 weeks ago



Where do I start to troubleshoot?

[firedemon]

a pop in the carb is usually ignition . coil , timing , points , or ign module in hei .

[In The Ten Ring]

My 1975 Pontiac does the same thing! *It's been parked since 2004* but it does the same thing.

It would start out fine and at low speeds, say 5 to 10 mph (pulling out into traffic) it would quit. I'd shift into neutral, restart, and it would be fine.

[hamjet]

Maybe water, condensation in the gas? when did you get gas last?

[OUbesto]

Filled tank about two or three weeks ago and was at 1/4 tank yesterday so I refilled about ten miles before second stall. Never had any other stall issues during the first 3/4 tank!

[garyd1961]

Sounds like something in the ignition overheating as mentioned in firedemon's post or maybe the hot wire to the ignition under sized or wrong voltage. Possibly vapor locking also.

Edit-Hamjet may be right, I've seen several cars towed in lately with water in the gas, they had just filled up also. The gas these days will suck water right out the air and if you happen to fill up right after the tanker fills the store tanks you will get a lot of water. As the gas sits the water will settle to the bottom but when the tanks are filled it stirs up the water which mixes with the gas until you fill your tank then it settles to the bottom again, in your tank.

[prodjay10]

Check for vacuum leaks around the carb base gasket and intake manifold as well as other vacuum lines.

[firedemon]

oh if it has been converted to hei check that the resistor wire has been replaced or bypassed it heats up and puts less voltage to the coil to protect the points . hei don't like less voltage and will give you fits

[OUbesto]

Good stuff guys...THANKS! I know what I'll be doing this weekend!

[wbc409]

If you are still running points, change your condenser. I had one go bad, the truck backfired so hard on the highway it blew the end of the muffler off. The only difference is the truck wouldn't stall.