2004 XC70, 120K. Oil pressure light came on after driving 15 min. Temp fine. After a half hour could drive again. Changed the pressure sensor and it did the same thing. Took off oil pan and replaced the pickup seal and the two oil pan seals. Still doing the same thing... I can drive it to the next town about ten miles and the light may flicker while parking. Obviously the oil pump lasts for the life of the car. 10w40 oil. What is going on?

 

How much charcoal/sludge was in the oil pan? Has the PCV system been replaced? (clogged pcv does not lower oil pressure, just is a marker as to what service has been done). Have you been using synthetic oil? (last longer, builds up less charcoal in the oil pan)

Did you replace the the oil pickup tube with the new style plastic tube with a tulip shape on the end?

 

I found my problem in other posts that I will try.

 

Hi. Yes, sludge problem building up on my oil pickup. I need to do a thorough cleaning. I found out about this on another thread. Thank you.