1989 Buick Century Thermostat replacement.

Thermostats are a simple replacement on most cars.  After a week of 5-10 degree temperatures it became apparrent that something was wrong with the Buick, no heat at all unless the vehicle is idling, at highway speeds the temperature just dropped. 

Thermostats are cheap and easy to replace, so it was a good starting point, of course the easy part did not hold true.  Most vehicles have the thermostat easily accessible at the top of the engine on head, just follow the large hose from the top of the radiator, but on the 3.3 liter buick century, the large hose attaches to a filler pipe that goes underneath the mass air flow sensor and intake throttle body, joy.... But wait it gets even better.

After finally wiggling and working my fingers between the exahaust and under the mass air-flow sensor, a new surprise, there is a bracket on one of the bolts going to the air-intake, and it was welded on !  Nothing a good hack-saw can't fix, as there was no way I was going to remove all that stuff.  After cutting the bracket, it was just a job of removing the bolts, which was not hard, but not easy, as there was not enough room to get a socket in there, so I had to use box wrenches with about 1/8 of a turn, argh.  Eventually both bolts came out, pipe removed, thermostat replaced, than the frustrating task of getting the bolts back in and putting here back together.

A close inspection of the old thermostat shows that it is in a stuck open position, which when it's 10 degrees outside and your moving at 70 mph, means no heat.  Now the Buick has heat.

The Bracket now cut: