Can be more than one problem.
You losing power when you have the backfire?
Water in gas, rebuild carburetor, getting water true manifold.
I just have the last one. I have to change the manifold and the problem when away.
If they respect you, respect them. If they disrespect you, still respect them. Do not allow the action of others to decrease your good manner, because you represent yourself not others.
-2001 Maxum 2100 SR2 Sport -1997 Regal 258 Commodore (Sold)