[ThePurplePanther]

Originally Posted by AllHailKingVolvo

I had this issue on my last 740 Estate. Different engine of course, but the same issue.

I changed the oil and fitted a Mann oil filter with the anti-spillback valve as per Volvo spec, and the problem was cured straight away. The oil light went out within half a second of starting, whether hot or cold.

This was somewhere around 200,000 miles-the Speedo had stopped working long before I bought the car at 170,000, and I easily did another 40,000 Miles in it. It now belongs to my mother in law who is tanking around in it happily and racking up plenty more miles with zero oil pressure probs, always using the Mann filters at every change.

Very good point... all hail the king!