I have a 2000 merc Grand Marquis with the 4.6 engine. The garage I go
to has tried to twice to change the thermostat but have been stopped
dead, fearful, that the bolts going into the plastic intake manifold are
going to snap off. If that happens they say that it would require a new
manifold and lts of expensive labor.
I have been in the garage on two other occasions when they have not been
able to remove the bolts on two 4.6 engines to change the thermostat.
What a lousey design problem in my estimation. Has anyone else had this
problem with those damned plastic intake bolts for the thermostat?