Vr6 problems, check for tappety engine as its a good sign of worn chain guides, check for coolant level as the crack pipes and t piece are prone to splitting, check for smoke for signs of worn valve stem oil seals/piston rings/head gasket... white smoke = burning coolant = possible head gasket, black smoke = burnin fuel = maf fault, temp sensor fault, lambda fault, or many other sensors that lead to over fuling, blue smoke = burning oil = worn valve stem oil seals, piston rings etc obviously check for bite on clutch isn't really high.
As said check for air bag and abs faults.
Take a jack, jack up on the front engine mount behind the splitter and check for play side to side as its a good sign of worn track rods/ends, also check sump for oil leaks etc while its up.
Check the full length of the sills, mainly the front foot or so, also while its up in the air check the floor bungs for any rust as these are really bad for them, mainly under driver and passenger carpets! Check rear too though.
Check for wet carpets = holes in floor or blocked rain gutters from sunroof, check operation of sunroof and all electrics while your at it!
Check for factory sticker in the boot, usable spare wheel, lock nut if it needs one, spare key?!
While its up check for Anything that may raise concern, ie overly corroded brake lines, bodges/quick fixes.
Important one, try to make sure the engine is cold on start, a warm engine can hide a lot and normally indicates it is, check the oil while its cold, and check the gear selection when running cold too.
Check the pcv valve isn't broken/bodged as these can lead to terrible mpg.
Check service history if poss and milage against the engine.
Oh! Check the two heater matrix pipes for signs of leaking at the bulkhead, they corrode and crumble away, leaving you needing a new matrix and no heating!!!
Obviously check that the car gets upto temp and stays there, that the fans kick in and that they remain on once the engines turned off, check for any knocking or banging during the test drive.
Oh really bad rust spots.... Front of sills as mentioned, lower of the front wings as the hold sand and moisture and rot from the inside out, if it has the plastic arches, you need to pull them away from the car and check for rust as they hold water!! Check the top covers on the sill covers as there made of metal on the inside and rot like mad.
Check the spare wheel well for water as a sign of leaking round the rear lights, also function of the rear lights as if they leak they lead to short circuits on the lighting system....
Can't really think of much else mate....
Just be thorough!!!!!!!
