What would cause my rx-7 to run up to 4K and even higher and run dead rich for like 30 seconds and then go down to idle? Does it soud like a particular problem? It smokes out the back and up around teh manifold too. I can not figure it out? I know when I took my manifold off I threw off the TPS. Can this effect this? I took out my plugs and they looked fouled?

 

Its supposed to go to 3k rpms for ~20 seconds when started. Its an accelerated warmup system.
Start car in gear (unless automatic) and it wont do it.