Skip the auto shop - Our mechanics make house calls

Q: Low warm oil pressure. New oil.

asked by on

New oil and filter. New pressure sensor. Once engine warms oil pressure bottoms out and oil light comes on. What could this be.

My car has 124000 miles.
My car has an automatic transmission.

A: Hi. In order for any liquid to have pressur...

Hi. In order for any liquid to have pressure, there has to be a restriction. The restriction in an engine is the oil clearance on the rotating parts. On a newer engine, it is roughly 0.0015 of one inch. This is the area that there is a pressurized film of oil that the crankshaft, rods, and camshaft ride on. As the engine parts and oil pump wear, the gap becomes larger and oil pressure is reduced. Oil pressure on every engine is at its lowest at idle and when hot.

Here are a few things to try. Install a Nissan oil filter. Some aftermarket ones are much smaller than the original and restrict flow. Double check the weight of the oil recommended in your owner’s manual. Using a thinner oil will reduce oil pressure. The higher the number, the thicker the oil.

Ok, you tried all the easy stuff. Now we have to dig into the engine. Install an oil pressure gauge to verify the actual pressure. Next, remove the oil pan to look for a clogged oil pickup screen. At this point you could remove a main bearing cap, or all of them, to look for an issue. The general condition of the engine can be physically seen at this point. The only way to inspect the oil pump is to remove it and take it apart. If the screen wasn’t clogged, and the accessible bearings measure ok, it’s time to replace the pump. If a new pump did not correct the issue, the engine will need rebuilt or replaced.

Your could try using thicker oil if the car is not worth any investment. This could have some negative effects on the variable valve timing. If the oil pick up screen is clogged, this will make the problem worse and possibly ruin the engine. If you need further assistance, I recommend you have a certified technician, like one from YourMechanic, inspect the oil light on your vehicle and suggest an appropriate repair.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Near Constant squealing sound from drive side front wheel.

Hi there. The squealing noise that you are hearing from the wheel is the wheel bearings with no grease in them. I recommend replacing the wheel hub assembly on the driver side front wheel. If you need further assistance with...

Q: Not sure if I should replace the spark plugs on my 05 xterra

Hi There, Generally, spark plugs on most cars today will last for about 100,000 miles or more, however it is never a bad idea to perform preventative maintenance and certainly in any case where the engine is running poorly or...

Q: Low voltage light on dash

This seems to be a common problem with Dodge, Chrysler, Jeep vehicles. Many of these vehicles have a fusable link wire that goes from the battery to the alternator. When this fusable link fails, the charge from the alternator will...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...