I’ve got 114,000 miles on the car and low oil light came on, brought to dealer and car was really low… no leaks or crazy smoking… dealer did an engine flush and oil change… now hear a new noise from under hood… not sure if it’s valve or something more clicking sound… how do I diagnose or trust a diagnostic without tearing down the engine and spending thousands??
Low oil pressure = Engine damage.
Remove the oil pressure sending unit/switch, and install a mechanical oil pressure test gauge.
Start the engine and watch the pressure on the gauge.
If the oil pressure is low or non-existant, look for a new vehicle.
You can’t but an experienced ear can. Considering that you let it run out of oil and then drove it, my guess would be bearing damage. A knowledgeable mechanic will recognize the sound. Bearing damage from loss of oil spells engine doom. I hope I’m wrong.
Your engine’s critical bearings, primarily the crank and connecting rod bearings, ride on a pressurized film of oil. Run them without that film, and they’ll quickly destroy themselves and eventually seize up solid. Many a connecting rod has been broken that way.
I think you may have just bought yourself a very expensive education.
The lesson? You need to monitor your oil and fluid levels on a routine basis.