1998 Volvo V70 XC Question: tune up

I would buy my spark plugs from Volvo, and make sure I gap them according to manufacture. If you call Autozone they have the specs for that in there computor if you ask. Your biggest chore is removing the plugs from the deep hole buy a 99 cent magnet at Autozone. P.S. I own this same car. retired army mechanic and former Autozone store manager.

Your car has hydraulic valves so no valve adjustment is necessary as part of a tune up. I would suggest changing the engine oil and filter, the spark plugs (I like NGK or Nippon Denso but not Bosch platinum). The fuel filter is under the right rear of the car but could be differed until later. The air filter is easy to replace your self and can be got at any parts store.
I don't know the mileage on your car but your engine has a timing belt that is critical to have replaced at its recommended service interval, and automatic transmission service is also important for long vehicle life.

Dont go to AutoZOne, they will do antyhing to sell you cheap, spark plus etc.

When your tuning up your car always use good quality items, the other quality is cheaper, but when they break or stop working it starts braking things and in the end you end up spending more money.