Starting, backfire issues with my carb'd 911E

[ckissick]

Over the summer, my 911E with a 3.0L and Webers developed a hot starting issues on hot days. I had been planning on addressing it over the winter, but hadn't yet, as the hot weather is over. But then it did it yesterday, when air temps were in the high 50s.

I drove to a job site, let the car sit for 20 minutes, then tried to start it. No go. Since I was at the top of a long hill, I tried to push start it. It wouldn't really fire, and when I put the clutch in, it would die. So I left the clutch out until there was a very loud backfire and a cloud of black smoke. But the engine started and ran fine.

Also, before this incident, the car was running slightly rough on acceleration, with popping and slight hesitation. After the backfire, it ran smooth. And when I got home, I waited 15 minutes, and then it started right up.

What's going on?

[snbush67]

Sounds like it is running too rich and the plugs are fouling. Or you may have some crappy gas. It is probably time to change the in line fuel filters as well.