I had a new clutch kit along with the cam belt changed in my 2007 Opel Corsa as routine maintainance. The car was driving well all along... even did 160kmh while driving to the mechanics workshop. After the new clutch was fitted and service done on the vehicle it started to have a serious vibration when I drove passed 80kmh. The mechanics inspected it and then changed the front Engine mount. The problem was slightly better since the vibrations now started at 100kmh. The following day we had the ball-joints replaced after going to check at alignment and they advised that they are the culprits of the vibration, everything else was okay. After replacing the ball-joints the vibration now starts at 120kmh. Can you please give an educated guess as to what may be the cause of the vibration since the vehicle was fine all along.
It could be:
- new parts
- parts removed and replaced as part of the service work
parts that may have been close to worn out that may have been stressed past their limits by the work
Or it could even be coincidental - your car is reasonably old and things can just fail.
Unfortunately this is just too broad. Sounds like the mechanics are going through diagnostics to figure out where the problem is.
If the vibrations are a result of the work done to the drivetrain, you'd imagine that the car would vibrate when stationary, in neutral gear, clutch out, being revved to the same engine speed as is required to do 100km/h (etc)
Given that the vibrations are related to motion and are reliably producible at particular speeds, you need to be looking at components that (rotate) when the vehicle is moving, and that could go out of balance.
This is where something as inane as "the work-experience kid bumped your car into the kerb and knocked a balancing weight off the wheel, when he was moving it around the shop" could well be the problem..
For the time it takes, I'd start with the easy things like checking the wheels are still in balance