Stutter,hesitation
 

Hi folks hope someone can help,my car has started to stutter and is hesitant on acceleration,still boosts but with hesitation, it’s mafless and o2 sensor has been mapped out, was running absolutely fine before,the only thing I done was unscrew the alternator bolt to fit the alternator cover,and sort out the lights for the gauges,the boost tube came out of the boost gauge so pushed it back in, apart from that no other recent work done,when I unscrewed the bolt for the alternator a bracket at the back fell out so put it back and I heard what I can only describe as the sound of a fuse blowing. On idle the car seems it wants to cut out and revs seem to go up and down.
what should I start looking at please. MY95 wrx import

any help appreciated.

Check all fuses first, obviously.

Have you had the plugs out? Quite common for plug leads or coil packs to be damaged.

Are there any fault codes showing?