I assume diesel?
Passats are a bit pricey compared to old Mondeos and they're also not quite as reliable as some would say as their electronics can be a git.
The VW engine itself is fine, its just that everything else attached to it isnt so good. Mine suffered turbo failure and was forever needing 'something'.
For the old Mondeo, listen for the 'death rattle' - thats the dual mass flywheel rattling away, a whirring sound, feeling through the clutch pedal. A new clutch and starter are usually required as the dust from the clutch kills off the starter.
Look for notchy feeling steering. This could be a worn steering rack
Make sure all the warning lights go out as they should - lots of older cars may have fault codes or SRS issues leading to flashing or constant warning lights - these can be MOT fails!
Flashing glowplug light whilst driving could be an injector failure, failing to start or running a few seconds then refusing to start can be camshaft position sensor failure. The list goes on. Rough idle can be the EGR valve but I've not personally had an issue with these on the Mondeo, just our Doblo, Vectra, passat etc etc.
Check estates' shock absorbers for leaks through overloading
Erm.. Fuel pumps are fragile, power steering pumps are not the best... erm, make sure theres no knocks going over speed bumps. Some can be explained by a loose exhaust, others are suspension bushes.
Make sure the switches work, the aircon goes cold, the heated seats dont short, the heated screens work etc etc etc etc etc.
130bhp models should pull like a train, 115bhp models puff and wheeze along. All can be coaxed into 49 mpg +
Make sure you prospective purchase isnt an ex taxi! switchgear logos shouldnt be worn off, steering wheel shouldnt be smooth, seats should be firm with the drivers side height adjustment motor still working. Rear bootlid should stay up.
Have fun!
