I suspect that your model has the electronic ignition with the old distributor/rotor arm system. The cap is prone to a build up of lubricant from inside the distributor which as the engine cools collects at the lower part of the cap, which on this engine is on its side. When the engine is hot, no problem, but when cold & warming up can cause misfiring or when under load, hicupping &/or stalling. Remove cap, clean inside with meths or similar. Check the elecrodes inside aren`t covered in verdi-gris. Next port of call is HT leads. In 20 years of owning Nova & Corsas with this ignition system those were the only problems I encountered. Oh, could be neglected plugs,