My 2000 grand prix is over heating and the heater wont work. We replaced the thermostat and a fuse for the fan.

Marvin

• 85242 Answers
• Posted on Jun 01, 2009

SOURCE: THERMOSTAT REPLACEMENT

You will need a 1/2" socket with ratchet, and a 1/2" wrench for the actual removal of the thermostat housing. First, remove the air duct from the air filter housing and the air intake connection to the engine. Set aside. Next, remove the upper radiator hose from where it connects to the engine by loosening the hose clamp. At the other end of this part where the hose was removed from is the "L" shape that houses the thermostat and bolts to the engine. This part (housing) has two bolts. The top bolt will require the use of an extension on your ratchet which you will need to insert between the water bypass pipe and the exhaust heat shield before coupling with the 1/2" socket. Loosen the top bolt. The bottom bolt will require the use of the 1/2" wrench, as the socket will not fit due to the location of the heat shield. NOTE: the bottom bolt only needs to be LOOSENED and not removed, as the housing has an open "C" at the lower bolt location allowing the housing to pivot upward from that bolt. After removing the top bolt and loosening the lower bolt, you can pivot the "pipe" end of the housing downward and carefully maneuver the housing out of its location. You should now see the thermostat. Clean surfaces of the engine and housing well. Insert the new thermostat with the "spring" into the engine and the "bell" outward. Be sure the seal is seated properly into its socket in the engine. Position the housing carefully, making sure not to move the thermostat out of position. Reassembly is the reverse of removal. In my case, I did not use any gasket seal. The thermostat has a rubber seal on it which works well on its own. Adding gasket seal may make removing the housing in the future more difficult

SOURCE: no heat or cold air from vents

either bad blower motor or lose wire to blower motor.

SOURCE: 1996 Grand Prix SE, cooling fans inop

try the fuse,if not that the wiring is bad from the fan to the switch.

SOURCE: 2003 grand prix blower control only works on 5, no heat.

you got two diff problems or more poss hvac control head, bad blower resister, bad thermostat, low on coolant, or plugged heater core

SOURCE: 1997 pontiac grand prix gt,the heat and defrost

I had the same issue, however my blower motor did not work at all, heat or AC, it just did not work. It was the blower motor resistor. When I took mine out, it was brown and melted. Got a new at the junkyard for a few bucks. Works great now.

Testimonial: "i have ordered a new one from rock auto.com. and i am waiting for it now,how easy is it to change it out."