'97 G.A. Heat problems

Okay, I have a '97 Grand Am coupe (2-door). Anyway, the heater only blows cold air. I currently have the dash ripped apart and I followed the wire that opens the valve a bit behind the controls and stereo area, that worked. So that wasn't the problem. I haven't done anything with the thermo or the core. The car doesn't get hot or anything, it just simply will not pump out heat or air conditioner. The fan speeds work, it'll switch from defrost to floor to vent and all that, just no temp' change. I need help, guys, it's cold in Indiana. Someone told me it could be a thing called a ... BlendorFluctuator? Never heard of it, but he says it controls some kind of valve. I was thinking it was that wire that opened something under the dash, but that works. I don't know, if anybody has any idea... Shoot it my way, I would much appreciate it.
Oh, if you think it might be the thermostate or the heater core, please gimmie an idea on where that stuff is at, 'cuz I have no idea. I was told the core is somewhere in the dash, but I couldn't find it. And the thermo' is underneath the tube going from the radiator to the motor, couldn't find that, either. I'm not completely car-stupid, just the new ones have so much crap on them and they're so compact...
Thanks, Jon.

Welcome to AF MX6sRock !

Yes Indiana has been cold. :grinyes:

What is you engine size ?

First does the temp gauge(on the dash) work and what does it read?

If you can reach the heater core hoses, located between the engine and firewall, then see if they feel hot after the engine has warmed up. They'll be two going into the lower middle of the firewall.

I'm going to take a big leap here and assume you have a 2.4, given your description of where the t-stat is. If so, to remove the thermostat, look down on the back side of the motor between the fingers of the exhaust manifold. You can see the top of the cover and one of the bolts, should be a 9mm socket to get that one off. To take the other one off you can either crawl under the car or reach around the exhaust manifold, either way its going to be trying on your patience. There is also a bolt on the bypass pipe beside the oil pan, 13mm wrench should do it. Thermostat only goes in one way, the quad motors are impossible to put the thermostat in wrong. Good luck. If you need pictures I can go take a few, but they are going to be from a 95 2.3, but most of the components are in the same place.

Ya Skii I was thinking about geting this 95' 2.3 someone has.
It needs a head/gaskets/thermostat, and a fuel pump.
I told them I'd give them $200 , they said "takeit, its yours" :lol:

Kinda screwy they put that thermostat on the bottom of the motor anyways.

my dads '99 Caddy had a similar issue with a vent not opening and allowing the air to mix correctly. He ended up disconnecting the two battery cables and touching them together for a few seceonds effectively resetting the BCM and correcting the problem.

my dads '99 Caddy had a similar issue with a vent not opening and allowing the air to mix correctly. He ended up disconnecting the two battery cables and touching them together for a few seceonds effectively resetting the BCM and correcting the problem.

I dont see how the powerless cables could have reset anything.
If anything it was from the disconnection its self, not the toughing of the two.

Automobiles electrical systems are highly sensitive these days. :grinyes:

Simply disconnectng the battery cables will not clear the memory from the BCM/ECM as they have capacitors that store enough energy to retain some "learned" memory. When you hold the two cables together it drains these capacitors which erases this short term memory and allows the ECM/BCM to start over with all the factory settings.

my :2cents: says its the thermostat, since its cold up here now your not overheating because of the cool outside temp, also telling which motor is in your car is the most important detail you can give, if its a 2.4l the thermostat is in the metal pipe that wraps under the motor (like you said).

if it was the thermostat I believe it at least would get some warm air blowing through it. The way I read it there is no hot/warm air comming through.

if it was the thermostat I believe it at least would get some warm air blowing through it. The way I read it there is no hot/warm air comming through.

Not if the thermostat stuck in the closed position ... if the coolant isn't flowing its not going to get to the heater core, therefore your not going to get anything but cold air.

sorry Jim im not seeing where what your talking about would work, there is no electronic valve that keeps the coolant from flowing thru the heater core, the temperature of the air is controlled by a cable asembly which he says is working ok, maybe on a cadilac but not a grand am. Either im missing something or its not going to help disconnecting the battery cables. He mentions it changes from heater to defrost ok, so its not a vacume leak keeping the doors in the vent system from working. I would try the thermostat since its the easiest to get at, the only other option I see is that the vavle that the cable hooks to under the dash is broken and the arm is moving but not the valve.

if the thermostat is stuck closed the engine would overheat and as was stated previouly the engine was not running hot. As for the cable actuated vent door, what is the cable hooked to? I figured I'd chime in here and tell what my dad was able to accomplish by simply doing a two minute procedure. If your cars BCM does not operate the vent doors then no harm done.

Simply disconnectng the battery cables will not clear the memory from the BCM/ECM as they have capacitors that store enough energy to retain some "learned" memory. When you hold the two cables together it drains these capacitors which erases this short term memory and allows the ECM/BCM to start over with all the factory settings

I dont think so, thats :bs: !
Just asking to toast something here guys :grinyes:

With this year/model of GA's the heater cores are bad about pluging up and circulating little if any coolant through the core.
Simple way is to feel the HC hoses when the engines hot.

And with the Vent door, when the car is Off and the key on,
select through the heat/defrost/vent knob and you can here wheather or not the door is flapping.

Just my :2cents:

fry something with the battery cables disconnected, come on. Anyway I don't believe this '97 GA is anymore technologically advanced then a '99 "De Ville. I'm a shade tree mechanic and as such I tend to do things that have worked for other shade tree mechs 'cause we do not have access to the shops high dollar machines.

Not fry in the sense you are thinking with DC current.
More of the static discharge from connecting the two is what I was refering to.
Sometimes you get lucky, and dont burn something up,
but at the cost of most electronic devices its best not to take those chances.

If you are bored, you can read this about Electrostatic Discharge(ESD) (http://www.reade.com/Safety/esd.html)

I've killed more then one computer/electronics device from static :grinyes:

Well I never heard of anything about doing that in 6 yrs at Lincoln Tech or in the years sense :dunno:

And I dont see his troubles being anything electronic anyway :grinno:

Electro static discharge is prevented through grounding of a system, by touching the two cables together (disconnected from power source ie: battery) you are essentially grounding the system, thus perventing ESD.

Well Jim,
touching the two does nothing of the sort as for grounding. That would only be when the battery is connected that you could "ground it out". :rolleyes:

Plus Thiers no capacitors big enough in the 97 to hold any juice in any of the capacitors to begin with.

And to add, the Caddy you speak of is Chevy, and second its about 100x more advanced then the 97 GA .

Said Caddy('99 Sedan De' Ville) had a Northstar engine in it. About the only thing chevy about it may have been the chassis. I never said that the GA had the same BCM, I inferred that if it had a similar system then doing what my dad did may correct it, if not, no harm. easy enough to try.

Wow, for a minute I thought I warped back in time to 3rd grade with the banter going back and forth. Anyway, check the heater core for flow by grabbing the hoses near the firewall when the motor has been run long enough to heat up, just be careful not to burn yourself. If the hoses are warm at the firewall, the heater core is not clogged and you have a different issue. If the hoses are cold at the firewall but warm on the other side of the plastic junction in the hose assembly your heater core is clogged and needs to be replaced. If the heater core is ok, disassemble the lower part of the dash and evict the mouse that is living on the heater core and remove its nest. Good luck.

Wow, for a minute I thought I warped back in time to 3rd grade with the banter going back and forth. Anyway, check the heater core for flow by grabbing the hoses near the firewall when the motor has been run long enough to heat up, just be careful not to burn yourself. If the hoses are warm at the firewall, the heater core is not clogged and you have a different issue. If the hoses are cold at the firewall but warm on the other side of the plastic junction in the hose assembly your heater core is clogged and needs to be replaced. If the heater core is ok, disassemble the lower part of the dash and evict the mouse that is living on the heater core and remove its nest. Good luck.


YA skii, i htink we've answered MX6sRock problems.
We're moving forward now :D

Wow, for a minute I thought I warped back in time to 3rd grade with the banter going back and forth. Anyway, check the heater core for flow by grabbing the hoses near the firewall when the motor has been run long enough to heat up, just be careful not to burn yourself. If the hoses are warm at the firewall, the heater core is not clogged and you have a different issue. If the hoses are cold at the firewall but warm on the other side of the plastic junction in the hose assembly your heater core is clogged and needs to be replaced. If the heater core is ok, disassemble the lower part of the dash and evict the mouse that is living on the heater core and remove its nest. Good luck.


YA skii, i think we've answered MX6sRock problems.
And We're Graduating now :D