hi guys my N reg GTO has suddenly started showing as overheating on the gauge and the oil pressure is really low too.
I have checked coolant and oil levels and they are all fine and clear as well with no signof any mixture in them.
Can anyone advise what to start looking at ? oil pump? water pump?
The fact that the oil pressure is low and the temp is high makes me want to think its the oil pump but I am not a mech.
any help?
First things first, check your water level, then check your expansion tank. Next on the list is the thermostat, take it out and see if its stuck closed. You can check its operation by slowly heating it up in a saucepan and watching for the temp it opens at, oh you need a thermometer too. Next on your ever growing list is have you a leak anywhere, actually that should be the first thing to check. Is there a leak from your water pump, have to take off the front engine covers to check this, or look for rust by the bottom pulley. Most likely be a thermostat.
It hasn’t boiled has it?
The oil pressure gauges on these are not accurate so don’t pay too much attention to this, however…check the other stuff first 
Terry 
When was it last serviced as old/burn’t oil can cause low oil pressure I go by 3 oil colours light brown = good, dark brown = think about changing it soon and black = spent. On the over heating side does the fan kick in when she gets hot could just be a faulty switch
Mark
thanks Terry no it hasnt boiled yet. will check the stuff you suggested.
last time I checked the water level and oil level and they both seemed
fine. Just that I read somewhere that a bad oil pump stops pumping to
the top of the engine and the internal friction causes more heat than
usual hence the temp rise ?? I can actaully see the pressure gauge going
down while the temp gauge goes up
Hi Mark , the oil is rather dark and yes the fan kicks in when it starts heating up. The temp gauge rises as I drive along (not stuck at any level) so I’m inclined to believe the gauge still works.
Hi you can try to flash coolant system as it is maybe block so don’t let water circled probably in system.
As rust meal get in way and they block systems.
Do good flash and use air compressed air to clean and clear all pipes or you can use jets wash.
Make sure clean all pipe one by one and radiator.
Than replace new thermostat .
Cheers
Hi this is cheaper to check if it’s possible to sort out your problem by flash system.
If problem still same after doing all this than your problem need to replace water pumps cheers