Oil pressure low suddenly

Oil light comes on when idling because the oil pressure is low or restricted. This could be due to a clogged oil filter or oil pan strainer.there are several other reasons, these would require more information.Has the car had an oil change?What is the mileage of the vehicle?

You need to find out why you have low oil pressure. It is normal that as engine rpm's increase, the oil pressure will rise- the oil pump is moving oil faster. Even though your light goes out, you could still have critically low oil pressure. There should be sufficient pressure at idle to keep the light off. The light will come on when your oil pressure is almost nil- I believe for some it's as low as 8 psi. Normally, oil pressure at idle is specified anywhere from 15 to 40 psi. You would have to check specifications for your Expedition. To verify oil pressure, hook up a mechanical gauge at the oil pressure sending unit on the engine block. Check with a local shop.

The causes run from easy, simple to budget busting ruin. Low oil level, wrong grade oil, real old oil, oil leaks, internal oil leaks, worn oil pump, worn crankshaft bearings. It was pretty common on older very high mileage cars to have a fluttering oil light at stops and idle. It was time for a rebuild, or time to look for another car.

this means a mechanical gauge test is required to check actual pressure warm idling if low below 20 psi then the oil pressure pump relief is stuck open or engine bearing are worn

The oil light is supposed to come on when there is low oil pressure, so when the car starts, the pressure goes from 0 to whatever (25-60psi depending on the engine). As a result, the light stays on for a few seconds at the beginning of the start cycle and is then supposed to go out. If the low oil pressure light remains on, then you either have low oil pressure or you have a sensor problem. If you have low oil pressure, you may need a new oil filter. If the filter was just replaced, then you need to get professional help because low oil pressure will wreck your engine in a hurry. Your engine's oil pump may be faulty and need to be replaced.

Hi:
Usually your oil light doesnt come on unless you have less than 10 lbs of oil pressure. You either have a bad oil pressure sending unit, or your engines oil pump is bad. The only way to verify your engines oil pressure is to buy a direct reading pressure guage and install it on your truck, or have a mechanic check your engine oil pressure. Eitherway, you need to do something soon, because the long term effects of running with low oil pressure will ruin your truck engine.

The oil light indicates that the engine's oil pressure has dropped below the minimum safe pressure. When the light goes out it suggests that pressure has been restored to a sufficient level for engine lubrication but this is nevertheless a bad sign.

I suspect that the oil level in the engine is too low and that the oil itself has greatly deteriorated and has not been changed for some time.

1. Check the oil level again, after the car has been standing for a few minutes, and make sure the engine oil level is at the maximum mark on the dip stick. If not then top it up.

2. Have the oil (and oil filter) changed in the car as soon as possible and ensure it is the correct spec viscosity oil for that engine .

3. Brake test the car to see if the oil light still comes on under braking.
If it recurs you need to have an oil pressure gauge hooked up to the engine (by an auto repair shop) to see what oil pressure is being achieved at various engine revs. If an independent gauge shows no problem with oil pressure then I would assume a faulty oil pressure sensor.
If the pressure gauge identifies a lower than normal oil pressure in the engine's lubrication system then the cause needs to be identified and fixed.

Sean

Hi,
That means LOW PRESSURE , not low in volume. Pressure is measured in PSI. The reason that your light comes on when you are at a stop is because your engine goes to idle at a stop and would normally have lower pressure. That doesn't mean you should get a low pressure light though.. I would have it checked by a pro right away as this could be your first warning before a serious problem.

Hopes this Helps,
RSMITH972278
P.S. PLEASE RATE ME

there is a big chance that your sensor is nedd to be replaced

the noise is the chain tensioner in the cylinder head between the two camshafts. it is a job for a proffesional shop. the 1.8t passats had an oiling problem and were fixed with a larger oil filter. some times you have to remove the oilpan and replace the oil pickup tube.