My son was coming home from college and breaks down. He said everything was fine, then no power. (he is not a hot rodder, just the opposite) When I got there, you could start it, but when you put it into gear, little to no power. I got it off the interstate, reved it up, drove it a little and the power slowly increased. I was able to get it home, ran really rough. Cruised btween 55-70 with the gas to the floor. Low speeds, it would hardly move. 82 with an automatic, 86,000 miles. Backfired at low speeds,too. Any clues?

 

Yeah, here's a clue: you lost leading ignition if you're lucky, or blew a rotor if you're not lucky.

 

yeah, sound like ignition or rear rotor. PM rx7doctor he had an 82 gs auto that had the same thing happen, and it was all ignition related, he may be able to talk you through it.

 

mm this happened to me randomly the other night... at the worst possible time too driving into a steep drive. leading ignition failed and there was NO POWER at all, although still driveable just lots of clutch slippage to get anywhere lol

 

I agree with the leading ignition theory. Check for spark at the lower plugs. There's a slight possibility of one of the cats being blocked. I say slight because I don't think power would increase, more likely it would decrease. As far as taking out one of the rotors goes, I doubt it. Pull the rear leading (lower) plug, and check for good sound, replace the plug, and repeat on the front rotor. Being an automatic, I don't think you"ll find this to be the problem. But heavy carbon build up is pretty likely, and you should do more frequent seafoam treatments or some other recommended de-carbonizing treatment.