I have recently had some acceleration problems with my '97 960. When I step on the gas, the engine seems to hesitate for 2-3 seconds before I get any power response. Also, I get this brief hesitation at high speeds, when I attempt to accelarate, such as on the highway. This morning, when I drove my car about 100 feet from the parking lot to a stop sign where the idle became extremely rough, bouncing from 700-1200 rpms erratically. I shutdown the engine and restarted and the rough idle went away, but the hesitation issue seemed worse and it seems to worsen every day. Could this be a dirty throttle body? Distributor cap? Plugs? I would appreciate any advice.

Thank you.