It's NOT fun to drive with nearly no heat, so the time has come for me to break down and replace the thermostat in my 2001 Pontiac Aztek.

Does anyone have an idea how to accomplish this feat? Considering the cooling system is not scheduled for maintenance until 100K miles (I'm getting close) and uses special coolant, I'm not sure how difficult this will be, however I'm not willing to pay upwards of $400 to have it replaced at the shop.

NOTHING is easy to do with this vehicle. Try replacing the battery!

Any assistance would be appreciated!

CaptainRich

First, are you certain your problem with lack of heat is in fact the thermostat?
Cooling system service is up to 100K. Read the fine print in the sales hype!

That is why I ask. What does the temp gauge tell you? System full? Hoses getting hot? Radiator and heater hoses...



Replacement is as follows:
1. Remove the air cleaner and duct assembly.
2. Drain the coolant until the coolant level is below the thermostat.
3. Remove the crossover exhaust pipe. Use caution: these bolts can be a bear!
4. Remove the radiator hose from the thermostat housing.
5. Remove the thermostat housing bolts and clean any sealer from the bolt threads.
6. Remove the thermostat housing, the thermostat and gasket
8. Clean all mating surfaces.
Reinstall in the reverse order, but put sealant onto bolt threads. RTV or "liquid" tape and let it set slightly prior to installing the bolts.
Refill system with a clean 50/50 mixture and let the engine run to purge trapped air with the bleeder port screw (on the housing in the picture).
After the cooling system has cooled again, double check the coolant level.

lgehner

Thank you VERY much, especially for the diagram.

Yes, we're sure it's the thermostat. The system was checked at my last tune-up and all was well. A mechanic friend since checked everything and advised she was 99.99% sure the thermostat needs replacing. Unfortunately, she is now in Iraq, so I do not have her assistance!

Guest

Call around for prices to do the work. If you are handy with a wrench and don't mind wasting half a day go for it. But, the reason is costs $400 at the dealerships inflated hourly cost is because it is a bit of a pain to do. When my Aztek was due for its 100,000 mile spark plug change I called around and the average cost for the work was $250. I decided to do it myself. Wished I hadn't. I know this doesn't answer your how to but I thought it worth saying.