Tom I would check your point settings before you start on the carbs. A dwell meter would give you a quick check. Also check your cap & rotor for cracks. Then check your timing including vacuum advance to see if there working. Now the carbs. did you get any new gas before the problem started? Water in the fuel will cause backfiring etc. The odds of both carbs having problems isn't usually going to happen. I would disconnect the linkage to one side or the other .Now slowly increase the engine to about 2500 RPM . See how the engine runs. Now do the other side and see how it runs. Hopefully you will be able to feel, smell or see a difference. That should help you find which carb. is causing the problem. If you find one that is causing a problem you probably have to remove it and remove the top to check for a bad float, or dirt in the bottom or even dirt in the needle and seat. Try this out in that order. Please let me know what happens. Good Luck Gary Barker tdcox wrote: >I had a great time traveling to Pigeon Forge, TN (about 200 miles) to the >"Shades of the Past Rod Run" show. There were about 3,000 cars at the show >itself and an estimated 10,000 cars on display and for sale along the three >mile stretch of city. Quite a spectacle. The 300F was extremely well >received and I was told more than once that if it had been judged, it would >have made the top 25 of all cars at the show. Maybe so, maybe not. But it >got more than it's share of ooh's and aah's. > >During the drive into the city on Friday night, I had a trip of about an >hour at idle. After that, the car never really ran well until I got back on >the interstate to come home on Sunday. It would stutter and pop and acted >like it was running on six or seven cylinders. It was also bad to backfire >in the city and even on the trip home when I let off the gas. I assume that >the plugs were loading up due to rich-running carbs, but it sure ran rough!! > >Today, when I took it for a brief drive to the shop, it wouldn't shift out >of first gear for several hundred yards. Any thoughts about this or the >rough running? > >The only other odd occurence was that the heater core fractured on the trip >to Pigeon Forge and it poored coolant onto the passenger floor. I rerouted >some hoses and took off down the road but didn't think that would affect the >running of the engine. > >Thanks for your help and suggestions. > >Tom Cox > > > > > > >To send a message to this group, send an email to: >Chrysler300@xxxxxxxxxxxxxxx > >For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm >Yahoo! Groups Links > > > > > > > > > > ------------------------ Yahoo! Groups Sponsor --------------------~--> Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/8LmulB/TM --------------------------------------------------------------------~-> To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/