At Fixya.com, our trusted experts are meticulously vetted and possess extensive experience in their respective fields. Backed by a community of knowledgeable professionals, our platform ensures that the solutions provided are thoroughly researched and validated.
High oil pressure, but no indication that the truck is running hot. At 40 mph oil pressure will be at 80 psi. When the truck is stopped at a light, the psi will go down to 48 psi. Is this normal?
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
Hopefully, it's just a bad oil sender unit, but, when the oil light flashes at stop signs and lights it's usually and indicator that the vehicle is either low on oil or you may be having problems with the oil pump. I would get it to a qualified mechanic ASAP unless you're qualified to work on it yourself.
You need to find out why you have low oil pressure. It is normal that as engine rpm's increase, the oil pressure will rise- the oil pump is moving oil faster. Even though your light goes out, you could still have critically low oil pressure. There should be sufficient pressure at idle to keep the light off. The light will come on when your oil pressure is almost nil- I believe for some it's as low as 8 psi. Normally, oil pressure at idle is specified anywhere from 15 to 40 psi. You would have to check specifications for your Expedition. To verify oil pressure, hook up a mechanical gauge at the oil pressure sending unit on the engine block. Check with a local shop.
The causes run from easy, simple to budget busting ruin. Low oil level, wrong grade oil, real old oil, oil leaks, internal oil leaks, worn oil pump, worn crankshaft bearings. It was pretty common on older very high mileage cars to have a fluttering oil light at stops and idle. It was time for a rebuild, or time to look for another car.
When you say it was "normal" with the engine off and the key on, do you mean normal as 40-50 psi, or normal, as 0 psi since the engine was off and there should be no oil pressure? This is important because if you are reading 40-50 psi with the engine off, it is not surprising that the gauge goes "too high" once you start the engine. If the gauge is at 40-50 psi with the engine off and the key on, then there is a problem with the gauge or the sensor. It is not an overpressure issue. As long as the engine seems to be running normally otherwise and is not clacking internally or other such things that would indicate oil pressure issues, I would feel safe using the vehicle until I could have the oil pressure circuit diagnosed and repaired.
No problem with the oil pressure, the norm is between 40 to 60. Anything lower then 40 you have low oil pressure and anything above 60 then you have high oil pressure which is caused by a blockage in the system.
What is common is the oil pressure gage fluctuating for the first 200 miles if the oil pressure sending unit is getting worn. Good maintenance will keep the engine clean and running good but the oil pressure sending unit is inexpensive and easy to replace. Next time you do an oil change you can have them change the sending unit.
Good luck and hope this helps. You can pick up the sending unit at Auto Zone and most auto parts store and will have the step by step to replacing it. If you do attempt to replace it. make sure you DO NOT USE any Teflon tape or silicon on the threads, they are tapered and need a good ground to the engine for proper readings.
Believe it or not....this is actually normal depending on which oil that you use. Some of the thinner oils will cause this to jump around and the thicker oils will make it jump around less. When you first start the truck the oil is thicker and will read a high psi then get lower with less rpm while the oil warms and then gets thinner then builds pressure again with more volume being put through the engine while you drive down the road hence going back up to 80 psi. This is typical winter issue with the Dakota's in general. I would only be concerned if the pressure bottoms out while driving or starting.
×