coughing/sputtering sound when given throttle

[cj8990]

my friends dsm sputters/coughs/hesitates

thats the only way i can describe it. It happens occasionally when given throttle but not all the time. Turbo has no shaft play and when you put it in 5th at a low speed a loud grinding vibration sound can be heard if you hold the throttle open not sure if this is related but its loud and you can feel the vibrations in your seat... engine seams fine under free revving and it also has other tranny issues (shifting into 3rd) so im thinknig its something with the trans.

let me know what you think.
thanks in advance

 

[fwd-ts1]

I had the same problem in my old car and it was the fuel filter.I changed it then it ran fine as for the grinding it sounds like the trans may be shot