cold start issues

[maxima21]

i have 97 maxima its a 5 speed with a cold air and a muffler....when i first start it the rpms go up to about 2500 then stalls. when i start it again the rpms stay at about 1600 for a few minutes... now one of the belts is squellin pretty bad. i thought it was the ac belt so i pulled it off to find it was only loose so i tightend it down and now the squeel is just higher pitch. so i am assuming it is the power steering belt. it always sqeeks when i first start it. i just replaced the spark plugs also.... no check engine light or anything like that... any thoughts?