Vauxhall vectra squeek.

Have a scan done, the faults should be logged in the ECU

check the pivot pin for the gear lever at the turret at the top of the box. you can check the shift rail operation her if you take the turret section and gear lever of the top of the box.

turn left pull out. un plug the wirs first.

run the fault codes and check for injector and fuel pressure problems

You need to test the fuel pressure and not guess, you have no idea really what is causing this problem without comprehensive diagnostics being done.

On this website (link below) you find fuse box diagram and description for Vauxhall Vectra C

Vauxhall Vectra 2002 2008 fuse box diagram Auto Genius

On this website (link below) you find fuse box diagram and description for Vauxhall Vectra C

Vauxhall Vectra 2002 2008 fuse box diagram Auto Genius

Change the MAS mass air sensor they get clogged and can cause the symptoms you are describing a clogged sensor prevents the engine breathing properly causing a loss of power and an increase in fuel consumption replace it

try lifting the brake pedal with your toes then switching on the cc when driving. sometimes a faulty or loose switch on the brake pedal can cause cc to cut out.

its your rubber strut mounts in the rear