I have a 92 da it is stumbling / surging when cursing on the hw if i slow down it will go away sometimes if i punch it it will go away thow the pull then come back when i am slowing down. my afr's will not even out i go from 12.3 to 16.1 when it is running smooth. it nurmly run at 13.9 and no there i no tune in the car. i have stooped till then i finger out what is up. i was planing or turbocharging it just a gauges are in the car at this point.
sk=stork
i have sk dizzy, wires, and plugs, walbo 255, sk map, pap head, tb, and intact manifold, 2 inch exhaust, with no cat just a test pipe.

 

someone has to have some idea on where to start timing, fuel, ignition