when i start my 88 bird in the winter the heater core area sounds like gurgling. no leaks not overheating just gurgling for a while. when it warms up after a few minutes its gone. any ideas

 

Blown headgaskets will do this ( suck water in the cylinder- force air into the coolant). A compression check will determine this for sure, if one sparkpluglooks new compared to the rest, it's been steam cleaned by the coolant in the cylinder and is a blown headgasket. The 3.8L engine is known for this problem throughout it's production.

 

thats what i thought but not a drop of coolant lost over ten thousand miles. not one leak, not one drop low. now fluid inoil or on dipstick. what do you think.heads were done last year.