How do you change a thermostat in a 1994 Pontiac Grand Prix?

Answer 1

This is definitely a harder change than it needed to be, but I'm sure it's nothing you can't handle. The first thing is to locate the housing where the thermostat is. You can do this by following the top radiator hose from the radiator to the engine block. You will find a round casting connected to the intake with two bolts in it. You simply remove those bolts and place a new thermostat in the housing clean off the old gasket material and place a new gasket and sealer on the housing and bolt it back on making sure to tighten the bolts evenly so you don't crack the housing. This all sounded simple, didn't it? The trick is getting to the housing because the air intake system is in the way. I loosened the air intake system and pulled it back and that took some time. There are some small water coolant lines underneath that were a pain to get off and back on. I replaced the factory clamps with some good screw clamps to help the next fellow, but there were still not fun. The air intake housing itself wasn't that bad as there are only two bolts that connect it to the intake manifold but getting to them wasn't real fun either. Seems I had to use a wrench because I couldn't get on it with a socket. Good Luck!

Tom

if you were smart, you would take it to the shop, but sometimes money is hard to come by, the thermostat is located under the exhaust manifold, remove it, but you must also get the 15 mm bolt underneath that holds the manifold to the block. If you can get underneath the car, that is the easiest way to get it. The alternative is take the nuts off the manifold, push it back, then twist the manifold to get the 15 mm bolt. After removing the bolt, I then used a zaw, and cut the exhaust pipe so I could completely remove the manifold. The only thing with that, is you need to put the exhaust back together. After doing this you should be Abe to replace the thermostat quite easily, but don't forget the little bolt that holds the water pipe up, it is just a few inches from where the rubber hose meets the metal. It fastens the pipe to the frame. I don't know who designed this car, but they need to be reschooled.

Michael