Jessee

Can anybody please help me ? I just wanted to know if anyone is experiencing the same problem as me and what could be the possible reasons for this problem to happen.
When i drive my car at 80km/h or above my car's engine starts shaking strongly but on below 80km/h the car drives smoothly. The problem started around 4 months ago and my car mechanic told me a few reasons for this problem to happen and i ended up replacing my :
1/Fuel filter
2/GDI fuel pump
3/Iridium spark plugs,
But the problem is still here and my next option is to change or clean the injectors.

apoopoo999

iTrader: (2)

we dont have GDI engines in usa but it could be a bad coil?

AWCAWD

Are you sure that the vibration is coming from the engine? One would think that engine related vibrations are not speed but rpm dependent. I would suspect either the suspension or the transmission. If your car has manual transmission try to drive at 80 km/h in a lower gear first and also at the same rpm that can be read at 80km/h in the highest gear. If it has automatic transmission try to put it to another drive mode (L or 3 or whatever you have available) and do the same thing. Most of all I would do a complete wheel alignment and would check the struts and the shocks and also the tires. If the suspension checks out fine then the transmission should be blamed. Hope this helps.