No oil on dipstick and slightly lower oil pressure

Checked dipstick it is bone dry. Ended up adding 6 quarts oil. Kept checking dipstick over the course or 24 hours and still dry dipstick. Truck was level when checking oil. I let truck run for 5 min after changing oil. I put oil in correct. Not seeing any leaks. oil pressure from dash reads between 20 and 40 when idling and driving. Oil pressure gauge not bouncing around.

My car has 173000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hello. If you are checking the oil at the dipstick and it is being added to the correct area then you more than likely have a serious internal sludge issue. If there is a lot of sludge then the oil cannot properly return to the oil pan. I typically remove the valve covers to inspect for this as there should be no other reasons why the oil would not return to the oil pan. If you need to have this problem checked out, consider having a technician from YourMechanic come to your home or office to diagnose the low oil level and make the necessary repairs.

How to Identify and Fix Common car Problems ?

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If you see no oil at the tip of the dipstick, that means your car needs to add oil, it is possible that there is some oil left at the bottom of the oil pan, or no oil left, because the dipstick is not touching the bottom of the oil pan.
Sometimes there are holes instead of marks. If the oil doesn`t reach inside the markings or holes on the dipstick, you need to add at least one quart of oil. If the dipstick is not showing an oil level, you need to add oil immediately.
Zero Reading

If this reading occurs at higher speeds it could mean one of three things: 1) the gauge is faulty, 2) the oil level is low, or 3) the oil pump (or its drive) is broken.

If the oil level on the dipstick is between “add” and “full,” a possible cause of low pressure would be worn engine bearings, especially if the engine has very high mileage. Excessive wear reduces the original flow restriction, which consequently drops the pressure.
Low Oil Level

The oil level dropping below the minimum dipstick line is one of the most common reasons behind low engine oil pressure. Your car`s engine oil level may be low due to an overdue oil change, an oil leak, or wear and tear. Without sufficient oil, the oil pump will not be able to generate enough pressure.

Low oil level is the most common cause of low pressure; it`s also the easiest to fix. Oil changes are important, and between oil changes, it`s equally important to regularly check your motor oil level and top it off as necessary.
However if the dipstick is left out for very long periods of time there is more of a risk of contamination. You should also check that the dipstick tube is clean… In some cases insects may nest in them, water might enter, and larger debris such as small pebbles, sand, etc may have found its way in.
Oil Level Is Too Low

The oil level dropping below the minimum dipstick line is one of the most common causes of low oil pressure. This can happen at any time, even if you`ve recently had an oil change. Over time, engines burn oil more quickly. This is due to piston rings wearing, seals leaking, and so on.

It sounds like your oil pump had gone bad. You may have spun a bearing and that is what the noise is. If you have a bad bearing, it will not allow the oil pressure to build to where is should be.
a worn or failing pump will cause a loss of oil pressure.
You should not take this situation lightly, as it is an indication that your engine has lost normal oil pressure. If you see this light on, we highly suggest that you stop driving your vehicle immediately and turn off your engine. Driving with this light on your dash can cause severe, irreversible engine damage.
When you have low oil volume or low oil pressure, you`ll commonly hear a “clattering noise” coming from the engine`s valves. This can come not only from not enough oil, but from the oil getting too old and starting to break down or foam.
Common signs include a low level of engine oil, leaking oil covering other parts of the engine, and puddles of oil under the car.
Reading between 15% and 40% absolutely warrants an oil change. Anything reading lower than 15% should be taken care of immediately. Oil change shops also use the car`s mileage as an indicator of when the oil needs to be changed. They typically recommend an oil change every 3,000 to 5,000 miles.
Pour in the oil – If the dipstick measured below the “Add” line you should pour in at least half of the quart of oil. You can use a funnel or pour it directly into the hole. Avoid spilling oil on the engine, as it will smell as it burns off, and be sure to wipe up any spills with a towel.
It can`t do any damage down there so don`t worry about it. If however you feel resistance then the broken piece is stuck in the tube and will need to be fished out or pushed down.
If you don`t take care to insert the stick fully, you introduce an error. And, sometimes oil clinging to the dipstick tube will cause an erroneous reading.
Using the wrong oil filter can negatively impact oil pressure. The wrong filter, a filter that isn`t working properly, or a filter that gets clogged can cause oil pressure to drop. The proper oil filter, along with the pressure relief valve, will help regulate oil pressure and avoid spikes.
When oil life reaches 0%, service on your vehicle`s engine is now overdue. By driving with degraded oil, your Honda`s engine may fail or significant damage may be caused.
Low oil pressure at idle only, will most often mean that the engine is low on oil. As more power is applied to the engine via acceleration, the pressure builds up inside the engine. Thereby causing the pressure to read as “normal”. High oil temperature can cause low oil pressure.
With the P0522 code, a low oil pressure issue like a low oil pressure condition will trigger the code. Faulty oil pressure sensors or damaged oil pumps can also cause any of these codes to be set.
It`s best to use the oil viscosity recommended in the owner`s manual, but using a slightly thinner or thicker oil (lighter or heavier viscosity) generally poses no long-term harm.
If you use your vehicle in urban conditions, often sit in traffic jams, drive at high speeds, and your car is old, buy oil with the 5w40 viscosity. But if you prefer calm driving, and fuel economy and eco-friendliness are important for you – choose a product with 5w30 marking.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

lost all oil pressure, replaced the oil pump, low oil sensor, oil pressure sensor, oil pan gasket,
ANSWER : The fuel pump will not stay on if you loose oil pressure. This is why it is shutting off. The loss of oil pressure may be from bad crankshaft bearings or camshaft bearings. The engine oil pan should be removed and the oil pump needs to be checked to ensure that you put in the pick up tube seal to the pump and connected the pump to the block. Then remove at least one main bearing cap and inspect the bearings for excessive wear and crankshaft damage. If you need some help with this, consider YourMechanic, as a certified technician can help diagnose the issue with your oil pressure firsthand and help you fix it accordingly.

No oil on dipstick and slightly lower oil pressure
ANSWER : Hello. If you are checking the oil at the dipstick and it is being added to the correct area then you more than likely have a serious internal sludge issue. If there is a lot of sludge then the oil cannot properly return to the oil pan. I typically remove the valve covers to inspect for this as there should be no other reasons why the oil would not return to the oil pan. If you need to have this problem checked out, consider having a technician from YourMechanic come to your home or office to diagnose the low oil level and make the necessary repairs.

Low oil pressure light comes on when idle. Check engine light is on as well. Both came on after getting an oil change 3 days ago.
ANSWER : It is possible that they put in the wrong viscosity oil. In rare instances, a defective filter will also cause low pressure. If there is too much oil, it will aerate and cause low pressure. Be sure the oil level is really not above "max". The P2187 code will appear if the oil fill cap is not tight but it will also appear due to a myriad of causes because that code only "generally" identifies a lean running condition. Consequently, numerous parts would have to be tested including the O2 sensor, gas cap seal, manifold air leaks, any vacuum leak anywhere including PCV and EVAP systems, exhaust leaks, and fuel system faults such as failing fuel pump, clogged filter and more. Since the car has relatively low mileage, you would not expect a failed oil pump, although the pressure sensor (or switch) could be bad. However, the occurrence of the oil pressure warning light is quite coincidental to the oil change, thus I would suggest bringing the car back and asking them to redo with a new filter and double check the viscosity of the new oil that they use. If the problem persists after that, you will have to test actual operating oil pressure (at idle for instance) as well as the oil pressure switch. Finally, if the oil pressure warning light comes on continuously, unless the warning circuit itself is malfunctioning, that means the oil pressure is too low to operate the engine without damaging it. Anytime the light comes on for more than literally an instant, you should shut down the car and thus an issue like this obviously has to be repaired.

If you’d like, a YourMechanic certified mechanic can come to your home or place of business to inspect the vehicle and perform an oil pressure light is on inspection to diagnose the vehicle and suggest potential repairs.

Truck has oil in it but when i am idling at a stoplight, the oil pressure gauge drops and says low oil 2003 Dodge Ram 1500 4.7L
ANSWER : Hello – assuming an adequate oil level, which you have checked, there may be a real oil pressure problem. It’s worth checking with a know working oil pressure gauge, so that you can get the real readings (i.e. 40 psi at running RPM, 10 psi at idle – both hot – would be acceptable). It’s expected that your oil pressure will drop at a hot idle, as long as you have good pressure above idle. Low hot pressures all around are indications of excessive connecting rod or crankshaft main bearings, camshaft bearings, or oil flow bleeding off elsewhere in the engine. For professional assistance, I recommend a low oil pressure inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

My car has low oil pressure. I’ve already changed the oil pressure sensor 3 times.
ANSWER : If you have replaced the sensor three times and it did not fix the problem, then you may have problems with the oil pressure being low at idle due to wear in the engine bearings. The reason it would be fine sometimes and not others may be due to engine load and temperature changes. Have the oil pressure tested at the sensor port to see if it is low and needs engine repairs.

I recommend having a certified mechanic, such as one from YourMechanic, come to your location to perform an inspection to determine why the Oil Pressure Light is on.

Are there accurate electrical oil pressure gauges that will beep me when my oil pressure goes too low and how do they work?
ANSWER : Oil pressure reporting systems with programmable audible alarms are readily available. An example is the CruzPro Digital Gauge but there are many other vendors and you really have to do a product comparison and look at all the reviews. Once you select an audible alarm based system, if you desire a professional installation, you can use YourMechanic’s oil pressure sending unit service page to request installation. Of note, most damage to engines related to oil starvation occurs in the few seconds after starting. Therefore, I would recommend you FIRST install a pre-pressurization system as that will give you the most bang for the buck and indeed solve what is an immediate problem in all engines. An example of this product is the Insta-Lube Engine Pre-Lube Kit. Again, though, there are many variations on this solution. I highly recommend pre-lube and the only reason all engines do not have it is such a system adds cost and complexity to motor vehicles but it solves a real problem. A certified mechanic from YourMechanic can install such a pre-lube kit as well, if you desire. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Hello Ben, my oil pressure is came on. Slight oil drip. Mechanic changed oil, replaced sending unit. Light came on after a day.
ANSWER : You need to have the oil pressure checked to see if the oil pressure is within specifications before you condemn the engine internal problem with oil pump or crankshaft and bearings. You may want to get the dealer involved now and let them take care of getting the light diagnosed.

replace oil pump and pick up tube
ANSWER : Hi there. Typically when the oil pressure changes based on the type of oil you are using, it’s an issue with the pick-up itself. Quite often, the wrong sized or style of oil pump or a pick-up line that is too short / long, can cause inconsistent oil pressure. It’s also possible as you indicated that the oil pickup screen is clogged with sludge or debris (especially if the engine has not been rebuilt). It might be a good idea to have a professional mobile mechanic complete an oil pressure light inspection to help you pinpoint the source of the issue and recommend the right repairs.