O.K. here it is.
I'm new in the RX-7 world and loving it.
Several months ago I was blessed with a '83.
Out side of a few things this car has ran great until now.
When I first start it up with the choke pulled out it runs a little rough but clears up when the engine builds up heat.
The real problem starts though when the car is fully warmed up and the choke is not used.
When going to stop at a light or something and I down shift the car will back fire until I stop or push the clutch in.
I thought that new plugs, wires, cap and button would help but that was only for a couple of days.
Please HELP! Where do I start?

 

Check for exhaust leaks.

Welcome to the Club and the Darkside.

 

leaky exhaust, timing, and running lean are all possibilities

 

try adjucting your carb its easy. pop you hood open and from the driver side if you take the air cleaner assy it will be easer you will find this screw on the side of the carb that is what you want to adjust just turn it one way and see its getting any better if worse than turn in the other way.

 

Check the first 2 before messing with the carb.

and Welcome.

 

Check thes two hoses. the big one would be more likely than the small one (brake booster vacuum). The larger one has a habit of cracking on the bottom elbow, and can cause issues like yours.

Good luck
Brian

 

Thanks everyone. I'll get back and let you all know what it was.