1997 audi a8 quattro

I have a 1997 audi a8 Quattro with 180,000 miles on it and for a while now the power and acceleration has been horrible ……i have to push down really far on the pedal for a while to get it up to a descent speed …and its kinda embarrassing ….especially at lights or a stop sign……freeway driving isn’t that bad but i can tell the power is nothing what it should be …..im thinking it could be the plugs or possible maf sensor but i changed the plugs about 5 months ago …..there is no check engine light on and no codes being thrown at all …..please help!!!