1995 Ford Mustang bad proformance

Engine Mechanical problem
1995 Ford Mustang V8 Two Wheel Drive Automatic 135k miles

hello,
i was looking to buy this mustang 5.0 and I took it out for a spin and it had very little power and the owner says its been seating for 2yrs and needs a tune up idled fine but no power. It didnt smoke nor knock just had very little power I tried slamming the pedal down and very little respond.