90' Maxima startup problem!! PLS HELP!!

Hi, My 90' Maxima hard to start in the morning after rainning. Today, I got to work, then try to start the car, there is cranking noise, but wont.(last night raining, high humidity). After I try for 10 mins. It finally start. I want to know what's going on? But after I change to "D" with the transmission(mine is AT), and then i push the gas, the rev of the engine running up and down around 1000-2000. The noise is like no enough electricity going through. Then i stop the car, while idle, the rev of the engine going down to 1000, then going up, then down to 1000.. repeatly. seems like no power. after 2 mins, i try to run again. after i stopped at the traffic light, then push the gas, rev going up and down, then the car die!! on the street. Then i try to restartup the car, and drive, same problem. Then I try to restar again, put it in "P" for 10 mins, then try to run again, now is smooth.
But I still dont know why? Any suggestion? I try to bring to the repair shop, they just said cant dupilicate the problems.

It sounds like your maxima has a electric problem it could be alternator or wiring you have to get it to shop and have it checked. Try to go to smaller shops (cheaper price and they don't usually say they can't fix it)

Try replacing the distibuter cap and rotor......replace it with a Nissan or Blue Streak....

Look to see if water or condensation collected under the cap....
Several year back I had a bad cap that would absorb moisture in humid/rainy day......I would have to remove the cap, spray it with WD-40 and wipe dry with TP.......

Finally.....if the plug wires are over 3 yr old....replace them also...it is cheap insurance....