Where is the thermostat on a Buick 3.8l engine?
The thermostat on a Buick 3.8L engine (series 1, 2, or 3) is located at the rear of the engine, on the intake manifold. It's usually housed in a thermostat housing bolted to the intake manifold. You'll need to look closely in that area to find it. Access might be somewhat restricted depending on the year and model of the Buick.