My 1990 Bonneville has been using coolant for about the last 15,000 miles. About half a gallon every 2-3 thousand miles. When I park it in the garage it does not leave a puddle, no coolant on the floor from the heater core, no oil in the coolant or coolant in the oil... where is it going?
I should have been concerned long before now, but I tried convincing myself that I was just working air out of the system for a while. But now that I have added over 2 gallons in the last 15,000 miles I am thinking something may be wrong. Is there any other kind of internal leak that could be happening that these engines are known for?