98 SL2 misfire - ignition module?

[WVN]

1998 Saturn SL2 (automatic, air), great car until 2 weeks ago. Drives perfect for 5 miles (from a cold start, see below) then 2 problems begin:

(1) Accelerating between 35 and 45 mph: hesitates, sputtering/chugging, lack of power, car starts jerking. Most likely to begin when going even slightly uphill. Slow down, or get it past 50, and the problems ease off.

(2) At a stop light, brakes on, idles fine for a minute, then starts bucking like a horse at the starting gate - shift to Park and it calms right down.

Problems are much worse if the fan is running ( not the AC, the fan ), turn off the fan when they start and they ease off. Can only run fan in Park at stop lights ! Very annoying in hot weather. Problems occur sooner if a warm start, after turning off to refuel or buy groceries, start engine after 10 minutes and it sputters at lower speeds before leaving the lot. 6 bottles of Fuel Injector Cleaner (1 with each fill up) and having Valvoline clean out the throttle (at regular oil change) doesn't seem to help, or only a little.

Friendly neighborhood auto shop says it's a misfire (sorry don't have the codes), needs a new ignition module, said "Saturn has a kit for this", and also replace corroded wires. Internet search found some recalls for Saturn ignition modules, but dealer says nothing for 98 SL2.

Looking at a $500+ repair job. Any second opinions ?? Thanks !

[Cat Fuzz]

Forget the module and start with a new set of plugs and wires. Also, make sure the coil tips are cleaned of any white powdery corrosion.