► Month nine with the Merc S500
► The faultless drivetrain is having issues
► Irritable and lazy throttle response
Quite suddenly, the so far faultless transition between fossil-fed and electric propulsion began to shed its inherent smoothness for more agitated manners. Cut-in and cut-out became irritatingly noticeable, throttle response varied from lazy to excited, part-throttle acceleration typically was a double-phased exercise. When I returned the graceful glider to its maker for a check-up, the man in blue smocks nodded knowingly: ‘A software thing.’ Sure enough, flashing the hard drive cured the problem. The only remaining drivetrain-related issue concerns the slow change from forward to reverse which is sudorifically reminiscent of early Ferrari F1 transmissions.
Logbook: Mercedes-Benz S500 phev
Price: €108,945
As tested: €154,890
Miles this month: 1481
Total miles: 12,509
Our mpg: 25.9
Official mpg: 100.9
Fuel this month: €401.13