The PNP sensor serves several functions, it tells the engine what gear range you selected, when to turn on the brake lights, when to unlock the gear shift lever, if it's o.k. to engage the starter, etc....

Not necessarily all of these functions go bad at once if the PNP sensor is malfunctioning.

If you row the shifter back and forth a number of times (engine off) and it clears up your issues, then yes, most likely it is a bad PNP sensor. A common problem. There are instructions in the FAQ's here on how to replace, as well I can send you a copy of instructions that I wrote up. Many on this list have replaced it. Not hard, just a bit of a pain and about $100-110.

I highly recommend only Mann or Volvo filters. FCP Groton sells them at a great price especially if you buy several. These engines (and transmissions) love synthetic fluid. M1 10W30 works very well in these engines, but you can also run M1 0W40 or 5W40 as well without problems.

As far a a manual for $100 goes. I would recommend buying an annual ALLDATA subscription for this car. 2nd year+ are cheaper than the first. $100 will last you about 4.5 years.

As far was the washer cap goes...... it is marked (if it's got the original cap). It's got the international symbol for windshield spritzer embossed into the top of it. You can run a marker across the raised portions if you like.

DEWFPO
--
1998 S90 077,400 and 1995 964 154,100