1985 Monte Carlo

[kohala55]

I have a 1985 monte carlo and I have put a new cap, Wires, plugs, fix Vaclum hose , and converter on mufler and when I give it gas it backfires I need some help. When I go down the interstate and give it gas it backfires, also it has been harder to start.

[Carleton Hughes]

Retarded timing or worn timing chain,check distributor timing with an appropriate timing light.

[C32AMG]

Bad ignition module or distributor.

[jnw86]

I would start with the basics, check the timing, make sure no plug wires are crossed. Does it have the factory carb? It could be as mentioned above, a bad timing chain, or maybe an intake leak, bad carb, etc.... Those symptoms can occur with an extreme lean condition. I would suspect the timing though.