I just bought a 2001 S40 t as a project car. 125k miles, replaced all brakes, tires, pass strut mount and wheel links. Any other ideas on what else I can do to smooth out the car as I still get vibrations when at idle? Also when I accelerate I hear a knock near the transmission area but transmission shifts great and once it gets going engine is strong...thanks!

 

You possibly have engine mounts that need replacing.

The knock on accelerating is indicative of the rear mount in probable need of renewal anyway unless the exhaust system is loose.

 

Hi and welcome to the forum.

Mounts!