Toyota Repair: Engine noise 1999 Camry LE, connecting rod bearings, valve seals

Question
Ted, I would like to thank you in advance for your help. I have recently discovered a problem with my wife's 1999 Toyota Camry LE 4-cylinder. It was about two weeks ago and I noticed a tapping noise from the engine. It had been longer than usual that I had changed her oil, so I checked the oil. There was hardly any oil on the dipstick, so I immediately changed the oil. I use synthetic oil only in her car, don't know if that matters. I have no clue how the car lost oil, when I changed the oil and noticed the drain plug gasket was dry rotted, but I notice no leakage ( did change the plug and gasket just in case). The only thing I can assume here is that the car is burning oil slowly but surely, or the oil eventually broke down or something. After changing the oil the problem still subsided.

Here's the problem, the car only makes the tapping noise at certain RPM's. In the PARK postion it does it at about 1500 RPM. before and after 1500 you don't hear it at all. When your driving it varies. Do I need a serious valve adjustment or is this more serious? I appreciate any help you can give me on this. Do you have any idea on about how much I should be charged to fix this problem. I live in Austin, TX, don't know if that will help how prices are.

Thank you ,

CHad Savoy


Answer
If the engine was run low on oil there is a good chance that the connecting rod bearings may have been damaged causing the noise, it's very hard to diagnose engine noises here for obvious reasons, that's my best guess.
Camrys have a tendency lose oil past the valve seals and I suspect that is where the oil went.
By the way, I used to live in Austin when I was a kid, my family moved to california in '65, have not been back since but someday I will.
Do yourself a favor and have one of the toyota dealers listen to the noise.