HELP!! with my 75 Dart

Have you had the underside of the car checked? How does the exhaust system look?
I was thinking of that too. I had a '84 Diplomat squad that somehow went backwards into a deep ditch at 2:30 in the morning on a -5 degree day. Car ran like crap, and I couldn't figure it out.. tune up, etc.. finally crawled underneath and the exhaust had a big kink. Fixed that and it ran great again.

Welcome from Wisconsin, @Beckers3405 ! You've come to the right place! Lots of knowledgeable people on here that like helping others out!