Volvo D2 40, oil pressure guage flat lines then comes good under 1400rev after warming up. Seems intermittent.
Any suggestions
Cheers

Depends on how the oil pressure gauge operates. If it's an electrical sensor/sender or a physical oil line to the back of the gauge. If it's electrical, it may be shorting, or the sender is faulty. Best check all the connections, and check for broken or cracked wiring. It could also be a blocked oil filter.

Thanks Michael, it's electric all seems good with wiring. Full service 100 hours ago. Cheers