Oil pressure light on

Hello
My 300tdi oil light comes on, when you rev slightly when engine is cold the oil light will go off but when the engine is warm the light will just stay on, also the water temp guage gets hot, near red when sitting at high speed 60 mph was thinking possible head gasket?
What are your opinions
Thanks

worthwhile trying a new oil pressure switch.

check rad has no cold spots, check pipes aren't rock hard, pump is working, enough coolant in it

Just put new thermostat and pump in so she's should be Good possibly a blocked rad and a oil pressure switch hopefully

Check oil level then get the oil light investigated first, if it is working correctly and telling you that you have no oil pressure it wont be long until you fatally damage the engine. Change the sender, quick start, if the same get a proper mechanical gauge on it to confirm oil pressure reading. DONT drive it with oil light on

btw, you can fit a pressure gauge easily enough and run it with the existing sender via tee

Replaced the switch and all sorted thanks!