2012 Grand Caravan - Code P0520

I've been getting a CEL code P0520 recently. I'm not sure what can cause it, besides the sensor itself having a problem, and I'd like to make sure I'm not missing something in my work. Here's what I'm seeing:

The Grand Caravan can display the oil pressure. When I first start it cold, the pressure goes straight to 96PSI, but no higher, ever. It remains at 96 for a few minutes. After a few minutes, the pressure is lower (low to mid 80s) when sitting or decelerating, but under acceleration it goes back to 96. After more time, the PSI when not under load might go as low as 67, and back to 96 under load.

Driving today, the oil temperature was 201F, and coolant was 215F. Recent history: I changed the spark plugs and one coil boot about 3 weeks ago. Also, on a mechanic's recommendation, I used Restore brand Engine Restorer, which I think (wishfully?) helped smooth the engine out somewhat. I changed the oil yesterday and reset the code, but now it's back.

I suppose it's possible I need to just let the oil run through the engine more. Or maybe I need to replace the sensor. Or something else, maybe? I thought oil pressure was supposed to be under 60PSI or so. Any suggestions on narrowing this down?


Update: Another source says that on a 3.6 Pentastar, the oil pressure can go up to 130PSI. That moves me in the direction of replacing the oil pressure sensor. Since the pressure climbs very quickly to 96PSI but will not go a single PSI beyond it, I think it's failing to measure correctly.

 

If you want to go with the odds, just replace the oil pressure switch. A faulty switch is the most common cause of the P0520.
If you want to test your switch, there are videos describing how to do this. You have a 3-pin switch.
I'd also be interested in hearing how you like Restore. Like all additives, it gets mixed reviews but seems to do good work in restoring compression by filling scratches.

 

I agree.....replace the switch. More than likely it's registering pressure too high for that engine.

There are many videos on that problem.
Several show special tools (sockets) needed to remove the old sensor and install the new one.

oil switch replacement video

 

Thanks for both replies. It looks like it's a pretty inexpensive part. I'm a little unclear on whether the part I'll receive will use the same socket as the one currently installed, but that should be easy enough to work out.

As for the Engine Restorer, my subjective view is that it works well. The engine felt a little smoother and a little more responsive. At the same time, though, the error code came shortly after adding it, so I wonder if it might have caused the current problem. I don't really think it did, but the order of events did make me wonder...

 

I had a really busy time for a while and wasn't able to get to replacing the sensor. I finally did, though. It's a tough replacement, mainly because of my XXL hands. I finally managed it, though. The CEL was immediately gone (possibly because of my habit of disconnecting the battery? idk.) The pressures shown on the information display were a lot more reasonable-- high 20's to low 60's, with a spike to about 70 under WOT. The losses of power that I wasn't really sure I was seeing are now gone. So far, so good. Fingers crossed. Next up... alignment. But that's someone else's problem once I hand them money.

It makes me wonder how the engine handles the faulty data it was getting before. Does it throttle back if the numbers it's seeing don't make sense?