My 98 v70 awd will not turn over at times other times it will and die out.It was running fine then one day after sitting a week would not start so it sat for a day or two more and boom started ran fine but would ie when i got on it.Today will not urn over at all getting 38 psi at the fuel rail 13.8 v on battery.I recently had the seal on the cam sensor replaced maybe they damaged the cam sensor?

 

Yes a faulty cam sensor will cause the older vehicles not to start. There was also a problem which the oil draining from where the tappets are causing them to not open the valves and makes it sound there is no compression. I would personally start at the cam sensor and work my way from there.