My car is a 2012 1.6 diesel Superb estate, 75000 miles. Oil pressure (red) warning light started coming on at the weekend. On Monday, I had the oil and filter changed. Warning light didn't come on for the journey home Monday but its coming on again today (Tuesday). I'm getting the sump dropped on Thursday to check the oil pump and especially the oil take-up pipe. Will get the sensor replaced at same time. I'll let you know how it goes. Anyone else had the same experience?

Thursday update: Warning light is (now?) coolant level, not oil pressure. Coolant topped up and all's well again. Was it coolant all along? I'm not sure. The coolant and oil warning light are right next to each other but very different icons. Here's the thing; the warning light came on at journey start, when the engine was cold, so I wouldn't have considered coolant temperature... and I had no idea the car has a coolant level warning (same warning light). Poor excuse though. Next time I'll check the icon and check the manual. You see all the warning lights when you first turn the ignition on, before start-up, and I bet most people don't know what they all are. I do now!!

P.S. Top marks to Fairway Autos of Hatfield Herts, who didn't charge me anything today.

PPS Oil and filter needed changing so no money wasted.

I've recently noticed my coolant level is down. (where does the fluid go??) are there any critical factors involved in topping up or will any good quality fluid suit?

Some coolant will just evaporate through the safety valve in the coolant cap, but you should also check the cap to make sure it isn't leaking through the rubber thread seal.  If you don't need to top-up much then you could just top-up with some de-ionised battery top-up water (available in most fuel stations).  If you need to top-up a lot, then you should get some coolant from a VAG dealer so that you don't end up mixing brands (and colours) of coolant, and use 50/50 coolant and de-ionised water.

Edited 7 November, 201411 yr by JakeBlade

Watch for a leaking water pump. My car did that and it needed the water pump and timing belt done. Luckily all on warranty though. If the leak contaminates the timing belt the whole engine is at risk.

My Superb 1.6 TDI (03/2011, 90000 km) warned me off "low coolant" year and a half ago. I topped it up, and it has been fine since. So I vote for the evaporation-theory.