I think if the previous owner had the heater core changed, did a full timing belt service, and a full PCV service using Genuine Volvo parts (or equivalent), then the car’s engine will have the capacity to get you through all of college and beyond. If these haven’t been done, look up tutorials on YouTube to assess whether you can do them yourself; RobertDIY and FCPEuro are good channels to look at.
Over time, you may be dealing with relays that stick, or sensors that begin to malfunction, and that will happen naturally since the platform is about 30 years old now (this isn’t exclusive to Volvo either, it applies to nearly every 90’s car). If you’re in the US, some sensors may be NLA from the Volvo dealer or other stores like FCPEuro/IPD, but you might be able to find eBay listings of them (you can also go to your local junk yard for parts as these cars are somewhat commonly junked). The best way to handle this is to be preventative before issues arise and while you have the time and means to do the maintenance. Some easy preventative maintenance that can be done right out the gate that I think is quite common and relatively cheap is:
- New fuel pump relay (easily accessible, and makes it easier to diagnose a bad fuel pump if you know the relay is good)
- New fuel filter
- New camshaft position sensor (car will not start if this goes bad, but it’s in a very accessible spot which makes it easy to replace if it hasn’t already)
- New BCS/TCV (if you have a turbo)
- New coolant expansion tank cap (aged caps will develop small cracks that can be hard to see)
- Replacing any torn-up air hosing (P80 Volvos are notorious for chugging through air leaks and not throwing DTC’s, but they perform much better when these leaks don’t exist).
If you want to go further down the rabbit hole, consider having the radiator and fuel pump changed out if they’re still original. You can also do a full ignition system service where you change out the spark plugs, ignition coil, distributor cap and rotor, but it’s honestly not imperative if you’re not experiencing misfires, and it won’t bring the car to a screeching halt like a leaking coolant system or broken timing belt/parts.
Personally, the biggest red flag for these cars is a poorly functioning PCV system, which is easily diagnosable by doing the infamous glove test and checking the hardness of the PCV hose that snakes out from the intake manifold and into the engine cam cover. A bad PCV system will lead to oil leaks, with the worst-case scenario being a rear main seal leak which is difficult to replace as a DIY mechanic. Second to this is a leaking steering rack as that’s quite an involved job. On higher mileage Volvos, like 200K+, you also want to be on the lookout for a significant amount of tailpipe smoke at idle as that may be indicative of the valve stem seals on their way out, leading to increased oil consumption – this will require either pulling the cylinder head off to replace the seals, or putting up with the oil consumption by making up oil as needed.