So recently replaced the oil filter housing on a 3.6 in a 2015 Chrysler 200s and all went well or so I thought, everything seems to run as it should after replacing but as soon as the car reaches 5000rpm~ or around there I get a check engine light and code po523 engine oil pressure sensor/switch high voltage. I’ve read it could be a few different things and I’m thinking I might just replace the sensor with the old one from the other housing that I know works for sure, but was wondering if this ever happened to anyone else?

 

if you got an aftermarket housing then yes the sensor that's provided they are usually crap

 

I just replaced my leaking Chrysler oil cooler/filter housing this past weekend in my 2015 Chrysler 200 AWD with 80,000 miles on it. It sprang a leak in the usual place (plastic welded round "port") and made a big mess with oil everywhere. I decided to replace it with an aluminum aftermarket one rather than buying another plastic one from the dealer. I bought one called "Feoie 926-876 Aluminum Engine Oil Cooler with Oil Filter Housing Assembly" from Amazon they actually have quite a number of good reviews, except there were many complaints of the oil pressure switch leaking, so I bought an aftermarket oil pressure switch from Rock Auto, the brand is WVE which is an NGK/NTK company and swapped it in. Googling seemed to indicate they are a good aftermarket parts supplier, in fact it says on the box Made in USA. Started up the car afterwards and drove it a few miles, got some high RPMs in, and all was fine. My daughter took it on a 70 mile round trip, all was fine. This morning she drove it to the local Starbucks and the check engine light came on. Interestingly, it had two codes, the po523, and a po441 (Evaporative Emission Control System Incorrect Purge Flow). This car used to have an issue with the Evaporative Emission Control System *constantly* throwing a code until I finally replaced the Evap purge solenoid, which finally solved the problem. I'm not worried about that issue, I've also heard sometimes it's a red herring. If it persists I'll check the O-ring where the evap line connects to the solenoid, it doesn't feel that "grippy" when you slide the connector back and forth, but I'm hoping that was just a one-off as it has been working fine ever since I replaced the solenoid.

Regarding the po523 oil pressure code, my plan is to give it a few heat/cool cycles and see if it becomes stable. If not, I'm going to take the sensor from my leaking oil cooler/housing and swap it into the new one. I'm not looking forward to tearing it all apart again, but if the code keeps popping up that's what I'll have to do. I'm just hoping I can get it unscrewed and swapped without having to pull the oil cooler housing back out and have to worry about draining the coolant and changing the engine oil, etc. It seems like there is room, but not 100% sure until I try to get a wrench or socket on it. I'll let you know what happens with my situation. In hindsight, I wish I had just swapped out with my old pressure sensor when I made the oil cooler swap (I debated it, sticking with a part I knew was good), but as they say hindsight is 20/20 and it seemed like a good part. We will see what the next few days brings. Good luck with yours.

 

Okay I thought I'd follow up to close out my experience. My problems continued with the new aftermarket oil sensors (pressure and temperature). It got even weirder, on another little trip, I stomped the gas pedal to boost the RPMs and see if the code would come back on, and the check engine light immediately came on (flashing this time) and the car started vibrating as the engine started missing - it was not pleasant to drive the car this way. I pulled over and plugged in my scan reader and found I now had a P0204 Injector Circuit Open Cylinder 4, and P0304 Cylinder 4 Misfire Detected - this was going from bad to worse! This was very strange as this car has always run perfectly in the time I've owned it (and yes I firmly reattached all the injector plugs when I did the oil cooler swap). I was afraid I'd have to drive it all the way home shuddering with a misfire, but when I cleared the codes and started it back up, it ran normally again. I decided not to rev it anymore and was now committed to swapping out the sensor. In fact I decided I was going to swap out both the oil pressure and temperature sensors and get the electrics back to what they were before I swapped out the bad oil cooler. The car had been running perfectly until I put in these aftermarket sensors as part of the oil cooler replacement, so my strong hope was that putting the original sensors into the new oil cooler would get things back to normal.

I pulled the upper and lower intakes back off and replaced both sensors with the originals from the bad original oil cooler (which I had luckily saved and had not thrown out yet). I was worried that there would not be clearance to replace the sensors without pulling the oil cooler off (with the resultant mess of oil and coolant), but I was barely able to wrench off the oil pressure sensor without having to remove the oil cooler. The oil temperature sensor is easy to get off but the pressure sensor is a bit more snug. Luckily my torque ratchet head is fairly thin (I don't think my other rachets would have fit so I was lucky and was able to tighten it with torque settings).

Since I reinstalled both original sensors back into the car, it's now running perfectly again, not throwing any codes . Lesson learned is to stay with Chrysler sensors, at least anywhere that you don't want to have to tear apart again. I'm surprised that the aftermarket sensors were causing so many electrical malfunctions in the car, but I am guessing as cars have become more like computers on wheels that voltage tolerance of any given part has become critical; kind of like upgrading a video card in your computer, mostly they're interchangeable but occasionally there is one that inexplicably is not compatible and causes problems, or a memory chip upgrade that has a slightly incompatible timing. If you're fixing/upgrading your plastic oil cooler/filter housing, either reinstall the original sensors, or buy new Chrysler sensors. Make sure to install them properly with high heat thread sealant. I let mine sit overnight after reassembling but before starting the car just to ensure the thread sealant had cured, not sure how critical that is but why not? Also, I went slightly lower than the specified torque settings on the sensors, I was very afraid of somehow stripping the threads and having to go through the horror/mess of draining the coolant and oil again and have to remove/replace the oil filter housing (somewhere I read of one person who did that on a plastic oil cooler housing). Even a little lower than spec'd it's very snug and not going to move. One nice thing was that no oil even dribbled out when I pulled out either the oil temp sensor or the oil pressure sensor, I guess it all flows back down into the oil pan, so there was nothing at all that needed to be cleaned up when swapping the sensors out on the installed oil cooler. Much different than cleaning up the oily mess that results when the plastic oil cooler fails.

Hope this helps someone else