thermostat, high idle question

The stat should not be causing the high idle. When you start the car, it runs in Open Loop for 30-120 seconds or so. At that time, independant of the coolant temps, the lambdas light off and begin fuel trim, even though your car is cold.

You dont lose much coolant but I could not tell ya a quanitative amount.

You could partially block part of the coil, etc, to keep temps a little higher.

Good luck.

Sounds like the t'stat has failed and is either open or partially open.

I'd drain the coolant low enough so you don't have to deal with it leaking out the t'stat housing. Having that area completely dry will allow for a much better/cleaner job when time comes to re-install the housing with a new gasket.

Tips --- 1) test your replacement t'stat in a pot of boiling water on the stove with a thermometer to be sure it's opening and closing as it should (180F is a good choice); 2) completely remove the upper radiator hose and the little bypass hose before removing the housing; and don't reinstall them until you have the new t'stat/housing back in place; having the hoses in place makes it dang near impossible to align the housing/get the bolts started; 3) be sure to get a gasket that's got the peel/stick adhesive on one side -- this will allow you to use the gasket to hold the t'stat in the housing during mounting --- MUCH better alternative than trying to mess with rtv, etc., or having the t'stat falling down and interfering with housing seal; 4) buy a new bypass hose too -- just cut the old one off -- much easier than trying to reuse that little rascal.