1980 360 Backfires through carb then stalls while in drive.

[dean941]

1980 - 360 Backfires through carb then stalls while in drive. Kind of like a Pop sounds the engine shuts off immediately and is hard to restart. Ive changed carb, plugs wires, cap,rotor, rans a direct line from a gas can to the carbureator. Yet still the same problem. I thought the carbureator would solve the problem but it has not................Any suggestions?

[MEK-Dangerfield]

Welcome aboard here Dean. 


  Sorry about the trouble. It could very well be electrical. Ignition box, or coil?  Let me ask you this, when you say it stalls in drive, is this when you first put it into drive, or while driving?


  Mike

[Bullitt-]

My 340/thermoquad did this from early on ..1975..You could ease into it OK but if you poured on the coal ..bang pop chug chug & sometimes would die. Rebuilt carb/replaced everything from plugs, wires, cap, eventually a new carb to no avail....turns out there were a couple of burnt exhaust valves I discovered in '79 when I replaced the heads.. no more backfire..
   I have another story from my moms '74 360 Monaco...similar symptoms that turned out to be the choke spring.

[dean941]

It runs perfectly fine; starts when cold idles fantastic, Drives great....However: It happens randomly while in drive;  while driving down the road (backfires once through carb engine shuts off)...Then after engine is off it wont start up for like 10-20 mins.. You can crank it and crank it and nothing..then 20 mins later starts up and you could drive 10-100 miles till it happens again...Very strange..(Could it be some sort of emmissions control stuff) I will try replacing the IGNITION BOX then go from there...

[vinb]

If you have one of those Lean Burn Computers on the air cleaner that could be your problem..Its been a long time since I mess with one of those....

[dean941]

Im not sure if it has a lean burn computer on air cleaner; does the 1980 360 come equiped with one...? This is a factory engine all but the basic replacement parts to date..

[Bullitt-]

Well the 20 minuite thing makes me think coil....if your gonna throw a part on try that 1st.
Also could be vapor lock in the fuel tank, is your tank vent plugged off?

[dean941]

I will put a coil on and then maybe a ignition box; in the near future, (both about 50 bucks) I have ran the motor with a hose running directly to a gas can with fresh gas and plenty of ventilation. I also Blew compressed air through all the fuel lines back to tank ect. Nonetheless; I am still on square one.

[Bullitt-]

Everybody needs an extra box...just in case....get a new ballast resistor to, only about $5.00
My car would start most of the time, then I was checking the resistance & voltage for someone here & my #s were jumping all over the place. New ballast & she runs better than ever.

[dean941]

I will try it and see what happens   

[Challenger6pak]

I agree with Bullitt.  It could be a coil.

[dean941]

Ignition coil or a pick-up coil????Which one do ya think???

[Bullitt-]

Ignition coil.