Oil pressure gauge not working correctly - high or low?

Hi,

When it dropped to 0, were there any noises from the engine such as ticking or knocking noises? If there wasn't, chances are it is related to the oil pressure switch.

Here is a link that explains different engine noises. I'm adding it in the event you did hear something.

https://www.2carpros.com/articles/engine-noises

I'm not sure which engine you have, so I selected a 5.3L which is the most common. The problem with this is the sensor is located under the intake manifold.

I attached directions below for replacement. However, we need to determine first if I have the correct engine, if there is any knocking or ticking when there is no pressure, and if there are any wiring issues.

Let me know.

Joe

See pics below.

Do we know the oil pressure is adequate? I.E. Manual oil pressure test.

Don't buy clusters on e-bay. I know customers who have been stung doing just that. Go to the GM dealer and order the cluster, and most of them have to be uploaded with a GM Tech II when the oil life monitor, etc. Are in the driver information center.

This way you don't have to be without a cluster for several days, and you'll get the updated version of the new cluster.

The manual oil pressure gauge would be put in place where the oil pressure sender is located. Once the test is complete, reinstall the sender unit.

Check and test the oil pressure sensor located at top rear of engine-see below

I would replace the oil pressure sensor, t is on the rear of the engine facing up. Here is a picture. If it is small, look for #1 in the picture.

Let me know if this helps. NOTE: This is for the 4.8, 5.3, and 6.0L. If you have something different, let me know.

Joe

If the check engine light is on or when it's on, there is a code set in the computer. What is this code?
Do not assume that this is an electrical issue. It very well may be an oil pressure problem. Try changing the oil pressure sensor or test the actual oil pressure with a gauge that is independent of the sensor.
The fact that you change the oil regularly does not mean that the oil pressure should be good forever. Let me explain how oil pressure is made in your engine.
Oil pressure is NOT made by the oil pump. An oil pump is a positive volume pump, meaning it moves oil from one place to another in one direction. Oil pressure is made by the all the restrictions inside of the engine. Bearing clearences, oil passages, bends in the oil gallerys and lines, and the strength of the oil pressure releif valve spring are some examples of these restrictions.
If some dirt or a piece of hard carbon deposit is clogging up one of the many oil passages in your engine, this will create a higher than normal oil pressure; because this makes the path the oil follows smaller.
Ok, back to your problem. Change the oil pressure sensor to elliminate any question of an actual oil pressure problem. We'll take it from there. Let me know how you make out.

Hello and thanks for donating!

You need to check the oil pressure with a mechanical oil pressure gauge first. Pressure should be 18 psig at 2k RPM. You could simply have a faulty oil pressure sensor / switch sending false readings to the gauge.

If that is the fault then yes its fine to drive, its simply sending a wrong signal to the gauge. It is located on the top rear of the engine. Always disconnect battery before making electrical repairs. Then locate sensor and disconnect its connector. Unbolt from location to replace.

Check the oil pressure with a mechanical gauge if normal replace the oil pressure switch abnormal could mean oil pump and engine bearings

Check oil level. Do you hear any unusual sounds from engine compartment? If OK suspect faulty oil pressure switch.