Old member back again

OK, has been about 10 years or so since I have been here or even driven an RX. That being said, just picked up an 82 GS one owner a few weeks ago and have been picking thru some of the usual bugs.

The issues I am having I am pretty sure are related, but not 100% sure.

Car runs beautifully 96% of the time except for choked start and decel.

On cold choked startup it seems to want to run on one rotor for about 20seconds or so. After that she runs like a swiss watch. New plugs, wires, cap and rotor ... only run ethanol free fuel and she has been somewhat taken care of mechanically.

The decel problem is if you try slowing down in any gear she wants to buck a little. This is worse in second and third than 4th and 5th.

I am thinking all of the symptoms are a related, but it has been a long while since I have been into the old wankles.

 

The jerkyness on decel could be from a bad shutter valve, that's pretty common. That would also cause performance issues as it creates a vacuum leak.

 

Could be a gunked up ACV.

The one rotor thing could be a couple things. Tiny coolant seal leak or a sticky seal. With a bad coolant seal it could act up after shut down and leak a tiny amount into the rotor that has to be burned once cold started making it seem like one rotor is running briefly.

With a sticky seal it will have low compression for a bit untill the centrifugal force forces it loose. Try dumping some Seafoam and carburetor cleaner down the carb and let it soak after turning the engine a few times.