Oil Pressure Problem
 

Hi, I'm having a problem with my 2008 Suburban 1500. What happens is upon starting the engine the oil pressure will go up to about 40 and then after idling for about 10 seconds will drop down to anywhere between 0 -10. While in park if I press the accelerator the oil pressure will go up to about 40 again but if I let off the accelerator the pressure drops down to 0 - 10 again. As I start to drive the pressure will again go up to about 40 until I stop at a light, at which point it will drop down again. Once I've driven for about 15 minutes the oil pressure stays up around the 40 - 45 range even if I stop at a light and will remain that way for the duration of my drive. Once the vehicle has sat for a while and cooled off the issue happens all over again. I changed the oil pressure sensor with an aftermarket one and the problem still persists. My next trouble shooting that I'm planning on is to put a direct reading gauge on it to see if the pressure is actually dropping or if the sensor is malfunctioning again.

Have any of you experienced this sort of behavior and if so, what was the fix?

how many miles on 'er? Post your engine please.

Have you changed the oil and filter?

Verify the pressure with a mechanical gauge and when you take off the pressure sensor, look inside to make sure there aren't any blockages.

Inspect the oil pickup tube.

It has the 5.3 liter engine and it has 188,000 miles on it.

I just changed the oil and filter about 2 weeks ago.

My next step is to check the pressure with a direct reading gauge.

The sensor and sensor screen are both new.

Is there an easier method to check the pickup tube than to drop the differential, etc?

experienced this is my 2005 Suburban start with clicking noise which was a lifter then oil pressure started dropping.. replaced oil pump(heavy duty) solved both problems. 150,000 miles