low idle

HELP!!! i'm so frusterated with my car it's seems like everything is going out at once 3 weeks before my new baby is due=( grrr...any how..my number 1 problem with my 99 olds intrigue right now is this idle business....somedays it takes a while to even start the car..while other times it will just pop off....but the idle keeps going up and down...and it will even just quit....i drive 5 miles to work and yesterday while on my 5 mile journey it just shut off 7 times. then i have to put in neutral restart and hope no one slams into me...the idle goes below 1 then just shuts off...sometimes it will just catch itself and pullitself above 1...when i have my pedal down it won't shut off. but it the idle isn't consistant..so sometimes it feels like the car is jerking...it's when i'm driving slow..intersections...driveway ..parking lots..or turns...we've already changed the spark plugs..which i must say was a real adventure..haha...and found that a pvc pipe thingy the rubber was split..so we replaced that..along with new tires and brakes..which i know has nothing to do with it.....any ideas..you guys seem like you know what the heck your talking about...i fix computers not cars..so i need input..please help me!!! i'll wait for my other questions=)

Might want to read this:
http://www.automotiveforums.com/vbulletin/showthread.php?t=134899

Yo i had the exact same problem when i first got my 99 intrigue about a month ago. The engine would just shut off for no reason and sometimes it wouldn't even start. I took it to many mechanics but no one could find anything wrong with it. Then i finally took it to the olds dealership and they kept it for 2 days untill they finally found the problem. Believe it or not it was the IGNITION SWITCH. It sounds to weird to be that but thats exactly what it was, a bad ignition switch.