The man issues with vacuum lines tend to go from the fuel rail around the motor to the back...they typically dry rot from engine heat and age. Very common issue on the 97-03's. Auto part stores sell a MAF & Sensor cleaner for a few bucks you can try that...and if that fails you can visit...

Morad Parts Company - 3800 Motors, Transaxles, & Stock Parts and he can hook you up with a good MAF on the cheap.