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Jeep Grand Cherokee - CEL Light Related to Oil Filter

I have a 2014 Jeep Grand Cherokee with a 3.6 liter V6 engine and 54000 miles on it. At roughly 43000 miles, the check engine light started coming on and with an error code of P06DD. I have had the Jeep serviced every 3000-4000 miles. I have had the Jeep to dealers who say it might be a number of things including a faulty oil pump that would cost $1200 to repair. However, they are reluctant to do anything since they cannot guarantee it would fix the problem. I have recently been changing the oil and filter myself using Mopar oil filters and full synthetic 5W-20 oil.
Through trial and error I have found that when the check engine light comes on, if I unscrew the oil filter housing cap and replace the same oil filter in the housing without touching the filter, the check engine light goes off after about 2 miles of driving. If I do nothing , the check engine light stays on. There is no difference in the performance of the vehicle when the light is on. This occurs about every 1500 miles.
No one can explain why taking the oil filter out and replacing the same oil filter turns off the check engine light or why it comes on. All the mechanics I tell this story to, look at me like I am crazy.
Can you help?

I found these reasons why a P06DD code is thrown:

  • Low or dirty engine oil
  • Faulty oil pressure sensor
  • Oil Pressure Sensor harness is open or shorted
  • Oil Pressure Sensor circuit poor electrical component

Not sure why the dealer wouldn’t hook a mechanical pressure gauge to the engine to see waht the actual pressure is. If they did that, tell us what they found. That would narrow it down. If the engine is running low oil pressure , it will shorten its life. I would start there and go where it leads me.

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The dealer identified all of these as possibilities including a faulty oil pump. As far as I know they did not do a pressure check, if they did they didn’t tell me. Since the car is out of warranty, they said any repair they made, they would not guarantee it would fix they problem. So they basically said they would not do anything and to ignore it.

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The odds of is being a faulty oil pump are near zero in my opinion.

Instead of going through a lot of expensive and maybe unneeded repairs or even an oil pressure test why not replace the oil pressure sender and see what happens. It’s cheap and easy.

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It was out of warranty due to time not mileage. Chrysler/Jeep would not cover it.

This engine has a variable displacement oil pump to improve fuel efficiency. The pump itself is likely OK. The mechanism to regulate the oil, maybe not. That is the reason to verify with a mechanical gauge that is not starving the engine of oil. If your dealer didn’t run this test, then you need to find a better mechanic, dealer or independent.

At the very least they should have replaced the sender.

It is easy for the dealer to tell you not to ignore it, they won’t be paying for a new engine. That attitude really ticks me off.

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Thanks for the feedback. I will follow up on your advice the next time the check engine light comes on.

Is the oil pressure sensor near the filter housing? Perhaps in the process of fiddling with the filter, you jostled the wiring to the sensor, temporarily re-establishing a good electrical connection.

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This is exactly the conclusion I am coming to and will be checking out. I have a feeling that I am moving the wiring around to make a connection and then the check engine light goes out. Thanks for the feedback.

First thing I would do is replace the filter. It may have a faulty oil pressure relief valve (PRV) that is causing low oil pressure in the engine. It could be possible that the filter has a PRV that is designed for a different grade of oil than what is specified for your engine.

For example, if a previous model year engine specified 5w30 but your model year specifies 0w20, the filters would be interchangeable physically but the PRV, also known as the bypass valve, would be designed to relieve at different pressures. You could have gotten the wrong filter by mistake, or the filter you have may have a defect in it.

BTW, if it is the filter, you may be doing damage to your engine so change it soon.

This engine uses a filter cartridge, not a spin-on filter. There doesn’t appear to be a PRV on the cartidge.

I’d still replace it. The media could be defective. Always go back to the last thing you did before the problem started.