This may seem like a stupid question, but am wondering what the Oil pressure gauge will tell you beyond that the car is low on oil. Been looking at getting a set of gauges and the oil pressure is usually more pricey than the rest. I would get Oil temperature to know when the engine is up to temp, but what else could the pressure sensor tell me that would be worth all the extra cost.

Any advice much appreciated, Jonny

 

It will tell you when your engine is going to go bang as if there is no oil pressure, there is no oil in the system...

 

An oil pressure guage will tell you when you are low on oilas James says but by then it is too late and the engine is already damaged. The dipstick is for telling your oil level.
Consider a combined oil pressure and temperature from Racetech. 50mm and two bits of useful information.

 

I think the point is. Is that when your oil warning light comes on - often it is engine bang time. Its often all a bit too late once the oil light comes on - as you have pretty well much no oil in your engine
Think of the pressure guage as a pre-empt. An early warning system if you like.
Sudden fluctuations in pressure can point to problems.
Low pressure on idle or on boost ect can give you a good warning of an impending problem. Perhaps oil being lost rather rapidly from somewhere.