93 Honda Accord Won't Start in the Rain.

Good Evening,
My cousin had just purchased a Honda Accord 1993 Manual Tranny and we noticed that the electrical system is causing some malfuctions. The obvious was alot of wires had been spliced into for a remote car starter and also there was an alarm in the car and some wires were left open causing the battery to die. I am able to make that specific repair due to my backround being in the electrical field however, the car in the rain starts when you apply jumper cables but as you apply throttle the car leans out and pops sounding like it has no gas going into motor and more you apply throttle the leaner it gets and makes a whooosssh sound from the intake. The car runs perfect on a nice normal day. We live in CT and the climate changes quite a bit. So the problem is, it runs great on nice day but when it's damp and raining or you wash the car it does not run right. Any information on this would be extremly gratefull as this is a time critical situation. Thanks in advance,
Joe M