Will a tune up fix this?
 

If I'm cruising at very minimal throttle and lower speeds, I get a little rough sputter. Kinda like this "brrrrrrrrrrrrrrrrrppppbrrrrrrrrrrrrrrrrrrppppbrrr rrrrrrrrppp". You know?
PO said it has newer injectors, it had been sitting for a while, mechanic said it needs to be ran and to put some fuel system cleaner (I used Techron with Chevron) in it. When I'm on the throttle it does not do it, just when I'm decelerating or just off throttle.
Will a tune up fix this you think? I'm not sure of most recent maintanence, maybe I should do a good change of all fluids, tune up and replace the hoses and oil return tubes the mechanic said should be replace at some point soon.
Keep in mind I just purchased the car about 2 weeks ago and the PO drove it maybe 500 miles last year.
Thanks all.:)

Which motor do you have? have your frequency valve checked.

Sorry, 79 911SC with stock engine. 127xxx miles.

Come on ya'll this is an easy one right?

I would also check my fuel presures and mixture. It's always hard to diagnose a problem via a written description of a sound. If it is a burble, it usually means a slightly rich mixture. If it breaks up and you can feel the car stumble, it's something else, like above, or maybe a too lean mix.

You may also want to do that tuneup, including new wires and plugs, rotor and cap.

Check gaps, or change plugs and then if not that, then wires I bet. Similat to a bad set of wires I had once except mine was more pronounced.