I'm at 38,000 miles and had the car for about 8 months. Any ideas on what the problem could be and how much it would cost? Thanks for the help

do you got an SES??
Maybe 2K2-2K3 owner can give you a TSB from nissan that solve the prob!!

I don't get an SES. I bought the car from a small used car dealership, but I've got a 4yr/60,000 mile warranty through a company called Ultimate Warranty. It's supposed to cover everything the factory warranty does, so would I be able to take it to a Nissan dealer for them to fix?

Mine was mass air flow meter. Big $ - easy to install. Got mine from car-part.com - $75 and 15 min. labor = camper!!!!

Does anyone else think it might be the mass air flow meter? I'm hoping it's something kinda simple, replacing the MAF meter isn't too difficult is it?

MAF is really easy thing to change!!
Isn't suppose to have no power when MAF is broken?
Can you still ride your car?
I'll say bring to the dealership, but at 38000miles it may be kinda pricey if they don't want to pass to repair under warranty!

dirty throttle body?

3.5 are not the smothest running engine at idle (the repair manual states the idle to be +/-50 rpms). IMO some of the hesation is the drive by wire throttle.