Question about 2000 Pontiac Montana

Open Question

200 pontiac montana looses heat and pushes coolant into the overflow

I recently ran into some heating issues with my Montana. Although the temperature gauge would read normal I still had no heat. Thought there may have been air in the system as the gentleman that I purchased the vehicle from had the water pump replaced. Was finally able to get heat coming from the system with the car idling but as I would drive it I found I would loose the heat again. It seems as though when this happens an excessive amount of coolant is being pushed into the overflow reservoir. I've flushed the system; put in two thermostats and have bled the system on numerous occasions. Really stumped on this one and if anyone could point me in the right direction it would be greatly appreciated.

Posted by Anonymous on


4 Suggested Answers

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

A 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
The service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Good luck!

Posted on Jan 02, 2017

  • 4 Answers

SOURCE: possible overheating, 2004 pontiac montana

Its definitly a bad reading, you would know if your vehicle is overheating, you can usually smell it right away.I would say its your temperature gauge sending unit is defective, check the wires to see if they are well connected or broken. ask a backyard mechanic for assistance.

Posted on Dec 23, 2008

  • 1024 Answers

SOURCE: 2002 montana the temp gauge stays in the middle

your heater core may be partially clogged up, when you come to stop the engine speed slow down and so does the water pump. therefore you don't have enough flow until you hit the gas and the engine rev up again

Posted on Feb 26, 2010

  • 580 Answers

SOURCE: replaced thermostat and water pump on a 2001 Pontiac Montana, also flushed system. replaced with proper amount of coolant, but heater still will not produce warm air. .

There is a mix damper inside your duct that controls the heat over heater core and ac evaporator that to your floor and one to your defrost. it is probable an electric actuator, that is not functioning properly. If yu can locate it and manually move it, you might have to remove the actuator motor first, you should be able to figure out your problem, I hope this helps! merry Christmas!

Posted on Oct 13, 2012

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

How come I have a bad smell when I start my 05 Pontiac Montana SV6 and heat won't kick in??

Any chance you have loose "fan" belts, they may be slipping and it smells like burning rubber? Or could be a bad coolant leak if the smell is like antifreeze, so not enough coolant to get to the heater coil. Have you checked your coolant level recently?
And perhaps all fluid levels need to be checked. Have you had it serviced by a competent well recommended Mechanic at the recommended service times?

Oct 09, 2015 | Pontiac Cars & Trucks

1 Answer

Have had thermostat replaced, still runs cold in the heater

air bubbles means head gasket.
how is the coolent level?
are you loosing coolant ?

Mar 23, 2013 | 2002 Pontiac Montana

2 Answers

No heat at idle. good heat when rpm increased. why?

It sounds to me like your coolant level is low. By increasing the engine RPM you speed up the rate of flow by the water pump and this will send some coolant to the heater core giving you heat. Top up the overflow bottle and this should help. you may have to repeat this more than once to get it properly full. Hope this helps.

Dec 13, 2011 | 2007 Pontiac Montana

1 Answer

2002 Pontiac Montana, No Heat, I put the temp control on

the cabel from the heat dial to the heater box behind the dash could be snaped or jamed thus not opperating the lever which operates the flap which open and closes the heat box next to the matrix. or if your coolant is brown in colour it could be your matrix is clogged with sedament and needs flushing out. or it could be your water pump not pumping coolant round your engine or it could be a knackerd thermostat i hope these will help you id start with the easyest first thermostat

Dec 17, 2009 | 2002 Pontiac Montana

1 Answer

Heater problems

Have you tried checking the coolant lines going into your heater core to see if there restricted, it could also be a bad water pump, or a worn or loose drive belt. It sounds like you have poor coolant flow goiing through your system. You might want to also check your coolant reservoir cap to see if it is maintaining the proper pressure. Good luck.

Mar 12, 2009 | 2002 Pontiac Montana

1 Answer

2002 Pontiac Montana Thermostat replacement

check the coolant level fiirst...if that is low it wont give you any change the thermostat you have to follow the top radiator hose to the the send of it you will see a clamp take it loose...then you will see the thermostat housing its held in place by 2 bolts . once you remove them you have the thermostat....make sure you clean all the old gasket material off both the housing and mount.also make sure you get a new gasket.

Jan 29, 2009 | 2002 Pontiac Montana

Not finding what you are looking for?
2000 Pontiac Montana Logo

Related Topics:

20 people viewed this question

Ask a Question

Usually answered in minutes!

Top Pontiac Experts


Level 3 Expert

77939 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22306 Answers

Jeffrey Turcotte
Jeffrey Turcotte

Level 3 Expert

8832 Answers

Are you a Pontiac Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides