I'd 1st suggest measuring the actual oil pressure with seperate mechanical gauge - this can be plumbed into the engine via the current pressure switch port - if you use a Tee piece you can keep the pressure switch plumbed in as well and so see if the low pressure light corresponds to a low pressure reading.
As its intermittant and you have no rumbling or rattling noises from the engine its likely to be an electrical fault so 1st check the connection to the pressure switch is bright and clean and check back along the switch wiring for any signs of damage to the insulation
As if the wire is grounded out at any point then this will also turn on the light.
If you do have a low pressure reading ( should be 4 bar (59psi) at 2000rpm) and to turn on the light it will be very low about 5psi then replace the oil pump and ensure that the pump pickup in the sump hasn't come loose or is blocked
Thanks, ***** ***** question I need to answer is : - where is the oil leaking from ?
The leak came from a faulty oil pressure switch . I have not come across that in 50 years of motoring but quite common according to the local garage who charged a very modest 25 quid for replacing it.I was worried that it would cost 100's as it was already up for sale.
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