[ianw1974]

I have a Saab 9-3 1.9TID (120bhp). When I started the engine one morning, it was very slow in running and thought it was going to stall but it kept going. Then it seemed normal after a few minutes once I de-iced the windows.

Up to about 50mph (90kph), everything seemed OK, but then any speed higher than this caused the whole car to vibrate quite badly. After the car warmed up, the vibration no longer occurred.

Last night I left the car in the garage, and drove it today and had no problems with it whatsoever. What's causing it to vibrate so bad when it's cold?

 

[ianw1974]

Could it be something with the quality of diesel that I have in my car that causes this?

Open to ideas, as for now I've no idea why it's like this.