2001 Ranger Edge 3.0 V6

Was driving to work yesterday. Was about 5 miles down the road, came to a stop. When I stepped on the gas again the engine was running VERY rough and the check engine light would come on if I got much more than idle RPMs.

I limped it home very slowly and let the tow truck take it to the mechanic for fear of doing any more damage than what has been done.

Mechanic called me today and says it just looks like it needs a tuneup. Plugs are gunky, etc, etc.

I'm sure it does need a tune-up, but I'm skeptical that this will fix a problem that came on so suddenly. I was expecting to hear something major had broken.

I can change the plugs and wires myself, get an oil-change, etc. But I don't want to throw extra cash at a tune-up on something totally unrelated...

Thoughts?