O3 mazda 6 no oil pressure

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The oil light means that the oil pressure is low. If the car is serviced regularly and the oil filter is not blocked, it will be the pump. Or the oil pressure sensor itself is faulty. Be very careful, driving a car with no oil pressure will kill your engine very quickly.

oil pressure senor would be my first guess.if that checks out possible oil pick up blocked
or worst case worn crank bearings but i doubt it at the age of the car
fuel pressure side of it, could be possible fuel pump

No, it is not safe to even have the engine running with the light on-your oil pressure must be low or lost-serious engine damage will result.
Check oil level, and if low add to the full mark. If light goes out, you may be alright. If light is still on with car running, get to a shop immediately for diagnosis.

Get enough space from undeneath the car. Get a wrench ( most japs need a 17.. or 19mm) a plastic bowl of at least 5-6 lt capacity, get underneath the car, unscrew the bolt that is at the very bottom end of the engine, carefully at the last twisting mm's not to remove it quickly cause you'll make a mess, let the old oil drain to the bowl, get up, unscrew the top oil cap of the engine, let air get in and provide equal pressure to drain the oil completely, and when it happens, screw to bottom bolt back, tighten it and make sure the copper sealing ring is in good condition, ( otherwise change with new one to avoid leaks), fill with new oil fro above, taking filling indications every while, to make sure you filled the correct amount of oil, start the engine and wait untill the oil pressure warning red light turns off, turn off the engine, fill to the desired point, close the cap, and ...........you're done!!!

Mazda say that if your Mazda 6 consumues less than a litre every 900 miles then it within tolerance.
However these cars have a complicated induction mechanism controld by lots of diffrent vacume pots that are inturn controlled by servos, when any one of these becomes faulty the pressure balance between the exhaust side of the turbo and the inlet side becomes inbalanced, resulting in oil being forced through the turbos bearings. Its that simple lol!
The first thing I would check would be the swirl control valve, In the inlet manifold, This gets fouled up by the exhaust gases getting recycled by the egr valve(exhaust gas recycler)
Sooty deposits mix with oil coming from your turbo and jam it closed restricting the amount of air into the engine, and reducing power as well as creating black smoke from your exhaust.
So my advice would be to get your egr valve proffetionally blanked off, and have your induction system checked over.
Hope this helps as I am sure this is a very common problem!

there is a safty switch on your car to prevent run dry just add oil and car should start the oil pressure well reset the switch no need to worry simple fix good luck CJ

There is a oil drain return from the turbo charger to the sump. If the sump oil level covers the outlet into the sump, oil will build excess pressure tin the turbo causing the sealing rings to leak oil in to the intake manifold. This would cause smokey exhaust and loss of oil. Try this. Drain the sump completely, refill with the exact quantity of oil to Mazda spec. Dip the oil and if the new oil level is lower than the full mark on the dipstick, you have found the cause of the problem. Mark this new level with a scriber or file and fill only to this new level. Hope this is the solution.

I believe you have to put in place of the oil pressure swtich that is already on the block of the engine to determine low oil pressure.

you need to do a compression test worst case scenario you might have to rebuild motor