At motorway speed (2000 rpm/100km/h) I get a very slight hesitation/stutter. On a 30 minute journey it happens maybe once or twice. It’s like I have very briefly eased off the throttle. No fault codes or other problems, the engine is silky smooth.

Was thinking about new plugs and/or coils but I don’t want to waste money. Any suggestions?

 

A misfire on the HT or LT ignition side would probably register on your scanner even it was not serious enough to light up on the dashboard. Could be a dirty or sticking injector which might not register. As a cheap first step, try running a tankful of premium fuel with a full does of good quality injector cleaner and see if that makes any difference.

Richard

 

And it never hurts to properly clean your mass air flow sensor....