454 missing

[76chevyc20454]

Hello, I am currently new to this site so sorry if i put this in the wrong thread category. I have a 1976 chevy c20 454/th400. i was converting it to a manual choke and the cord hit two electrical terminals on the firewall. They sparked a bunch and i pulled it off. After i finished hooking up choke it seemed to missfire in multiple cylinders so i pulled the dist. cap and the terminals inside of it was corroded and the rotor was rusted a lil so i put a new cap rotor and plugs and it ran the same. so yesterday i put a new HEI coil in it and it ran considerably better but still had a missfire, more sounded like one cylinder. so i replaced plug wires and that didnt help. im not sure what i did to it. my dad told me it shouldnt be mechanical because it ran fine just before i did the choke, but could it be? I dont no what else to do lol.

 

[foamypirate]

Hello, I am currently new to this site so sorry if i put this in the wrong thread category. I have a 1976 chevy c20 454/th400. i was converting it to a manual choke and the cord hit two electrical terminals on the firewall. They sparked a bunch and i pulled it off. After i finished hooking up choke it seemed to missfire in multiple cylinders so i pulled the dist. cap and the terminals inside of it was corroded and the rotor was rusted a lil so i put a new cap rotor and plugs and it ran the same. so yesterday i put a new HEI coil in it and it ran considerably better but still had a missfire, more sounded like one cylinder. so i replaced plug wires and that didnt help. im not sure what i did to it. my dad told me it shouldnt be mechanical because it ran fine just before i did the choke, but could it be? I dont no what else to do lol.

@HotRodPC let's get this guy some help. You are the engine guru

 

[HotRodPC]

Welcome to GMSB. Yep, you found the right category.

So it ran fine before this happened? No misses at all? Was the key in the on position when you had the wires arcing? If not there should not have been any power to the ignition system at all and it should been protected. Now that wouldn't mean that an arc didn't ground out to one of the terminals on the dizzy cap and maybe even make it through the rotor. Does sound very strange. Have you checked and rechecked your firing order from when you changed the cap and the rotor. You may have crossed 2 wires. That's exactly where I'd start. Check for the 1 8 4 3 6 5 7 2. I've done it before at least a couple times during a cap change.

 

[76chevyc20454]

Thanks for the help. I checked that today and they were all write so I started it again and gave it a good rev an it stoped missing so I do t no what the problem was but I took it on a drive and drove it hard and it ran fine