JPTL

DISCLAIMER: This is a DIY $7 fix if the issue is a gummed up oil pressure sensor filter, which is very common - at least for '07 MY 5.3L powered GM trucks.
'07 Suburban, 5.3 with 227k
As our '07+/- Tahoes, Suburbans and other 5.3L powered GM trucks rack up the miles, those of us who have vehicles that had conventional oil changes most of their lives will likely experience what appears to be an alarming and serious problem with the engine's oil pressure. In many cases it's not the actual oil pressure in the crankcase, but a bad reading at the sensor. And in many cases this bad reading is caused by a tiny gummed up filter - a $7 part.
Before you go to the dealer and spend $400+ to have them remove the intake and replace the oil pressure sensor, I suggest that you read about what often brings this issue about, even if you don't intend to replace the filter yourself.
Following up on this thread covering the steps on how to replace the oil pressure sensor in 20 minutes, and my post in this thread, I decided to replace the tiny conical screen filter that sits behind the intake just below the oil pressure sensor.
If you've determined that the sensor is bad, and are replacing it, it's a must to replace the filter while you're in there. In many cases however, the sensor is diagnosed as being bad (OBD code 0522) and many techs go to replacing the sensor. This is often not the issue as I experienced a few years ago and several thousand miles ago.
Conventional oil leaves deposits over time that eventually gums up this tiny filter, preventing oil pressure to make it to the sensor that sits above it. The lack of pressure at the sensor tricks the system into thinking that the engine oil pressure is dangerously low and/or that the sensor has failed altogether.
Below I've added the steps to replacing the filter (GM part 12585328) to the sensor replacement thread here.
Please keep in mind that although this is a cheap DIY, it's not for the faint of heart, ham-fisted DIYers on a cold day. This job is rewarding but takes patience, relatively small hands and some agile fingers. You'll be doing the whole job by feel as the sensor and filter placement aren't visible when your hands and/or tools are in there.

Step 1: Have the new filter on hand to get an idea of what you're replacing.
Step 2: Fashion an extraction tool. I used a plastic drywall anchor, a small screw attached to a piece of coat hanger wire. After you've made the tool, test it with the new filter to see how well it holds the filter. The idea is for the tool to hold the filter so that you can lift it from the hole. The filter simply rests in the threaded hole, so it lifts out without any effort.
Here's the little plastic anchor on the end of a coat hanger:



Step 3: Read the sensor replacement thread above and prepare to do the removal with the tools on hand.
Step 4: Once you've successfully removed the sensor, feel for the hole to get a sense of where you're going to be putting the extractor tool that you've made.
Step 5: Reach down with the extractor tool and guide it into the hole.
Step 6: Lift out the filter. Nasty, huh?






Step 7: With the pressure sensor and sensor removal tools easily reachable, go back in with the new filter held in your fingers. You aren't going to be using the tool that you made, as you'll never find the hole. Feel around for the hole and when you find it, make sure the filter is at the opening and drop it in.


The filter sits in the bore like this
Step 8: Reinstall the sensor per the steps in the above thread.

Suburban Dude

This is the best write-up I have seen on this topic. Thanks for sharing.

SD