Cold-start hesitation after 9C2 ECU software update
UNKNOWN OR OTHER, ENGINE
12 NHTSA complaints · 2026-03 → 2026-07
“After having the Service Campaign 9C2 ECU SOFTWARE UPDATE FOR THETA II EMISSIONS IMPROVEMENT, TSB 26-01-013H-2 done, my vehicle started having driveablity issues”
“After the installation of the Service Campaign 9C2 engine update, the car now seems to surge or rev up briefly at lower speeds like it can't find the right gear or is trying to briefly accelerate”
“Service Campaign Update 9C2 was installed. Since then erratic shifting occurs including up and down shifting without change in acceleration and deceleration or lag. This lasts between 1-5 minutes after initial vehicle start-up”