Oil drain plug or radiator? Buy a new plug at any auto parts store . Bring in the old plug to compair size.
in the botton of the oil pan
It is on the bottom, passenger side of the radiator.
60.00 $
Drop the fuel tank
Heater core leaking? Windshield seal leaking? Door seal leaking? Evaporator drain plugged?
just pops out using small flat head
Yes
100,000 miles
replace the leaking component
Replace the timing belt at least every 100,000 miles.
You should replace the water pump on a 1999 Toyota Avalon when it becomes worn out. You can also replace it when it begins leaking.
If it is leaking, then best to replace it.