advise wanted please

hey all, i have a 2002 series 3 gu with 3.0L motor, manual, it had oil leaking from around the seals where the injector lines go into the motor. i put in the mechanic shop to get them replaced, just got home and noticed the motor doesn't shut off straight away when i turn the key off and has a shutter. have had a bit of a read about other with similar problem and got a little confused, just wondering if anyone had any ideas why this is happening. is it something to do with the work i had done or just a coincidence.

a little info on car, only bought 2 weeks ago and noticed the oil leak when i got home with it. car has 230000k's on it. was told by previous owner he had a solid fly wheel recently fitted(i think that's what you call it). starts and runs fine. any input is appreciated. cheers

Take it back to the mechanic first Big Rig,
Seems to much of a coincidence to me.

will do that first thing monday, they are closed now, just seeing if anyone had any ideas on what may be causing it. cheers

X 2 take it back and explain whats happening now that wasn't happening before,
Grab some MAF cleaner from SCA while you're out and about

I'd get it back to the mechanic too. Maybe he's got some dirt into the tube when he's removed it to fit new seals.
Can't understand why it's running on though.