'76 Buick 350 -4 BBL backfires after tune up

Hi V8 Buick,

I replaced wires, ignition coil, ignition module, cap / rotor, spark plugs, fuel filter and air cleaner; and the car is running like crap. Cylinders 4 & 6 are a little rich, the others are fine. The engine idles a bit rocky, the car sputters on take off in drive and reverse. It also back fires while driving whether on or off the throttle. I cleaned the carb as well. I'm planning to install exhaust and header but hopefully I can sort this issue before installing the exhaust and headers. Any help is always appreciated. Thanks.

 

Yea you got wires crossed up

 

Check wires 5 and 7 . Most common crossed . But 4 and 6 could be as you mentioned alittle rich. .

 

I'll check in the morning.

 

try 4 and 6 are swaped

 

Yup, I've vote for 4 & 6 swapped.

 

4 and 6 were swapped. Car runs much better now. Thanks for the replies.