Van heater not warming up-any auto mech types?

[forgop]

So, my wife's van isn't getting hot despite running for quite some time. On occasion, it may finally begin to produce hot air after 15 minutes of driving. If it matters at all, the engine temp got over the summer related to a stuck thermostat and it was fine after that. I'm not a heating or cooling system guy at all to know if one would have caused another. Is this likely a bad heater core? I haven't noticed a coolant smell at all. Blower is fine-the air just isn't getting warm except the rare occasion it may start warming up after driving several minutes even after the engine temp is fine.

Thanks for any suggestions you may have.

[replicant_argent]

Put another stat in it.

[Bruins Fan]

First check to see if it is full of coolant,not just the expansion tank take the radiator cap off and look.
Be careful do it with the engine cold.

Check the temp gauge, if the temp is not coming up the thermostat could be stuck?

That's some place to start.

[tsolomon]

Sounds like a thermostat and it's a cheap fix if it works.

[T.G]

Does Lowe's sell anti-freeze?

[ninjavanish]

Echoing others who've posted already...

Sounds like it could be related to your thermostat.

The thermostat is going to open up, allowing coolant to flow freely to the radiator and heater core once the thermostat reaches the appropriate temp. This typically happens within a few minutes of starting the engine.

If it's stuck in the open position it is not allowing the coolant to increase in temperature properly because it is running through the raditator from the moment you start the vehicle.

This may account for why after a prolonged period of driving the heater appears to begin working again. It is simply requiring a much longer period of time for the coolant to attain a temperature sufficient enough to provide the heat into the cabin.

[forgop]

The reason I replaced the thermostat over the summer was because it stuck closed and had high pressure behind the thermostat as though nothing was getting through. You could squeeze the hose going into the radiator very easily, but the line going into the engine was as tight as could be.

It makes sense, but then it doesn't because I just changed it and wouldn't it seem unlikely to already be bad again so soon.

[neoflex]

Could have just been a defective part and since it was summer never noticed the heating portion of things.

[wayner123]

What model is your van? And does it have a temperature sensor on the dash?

[forgop]

What model is your van? And does it have a temperature sensor on the dash?

Dodge Grand Caravan-it shows the temp gauge in the dash. Prior to replacing the thermostat, it was as high as it would go and one day I even stopped and pulled off several times to cool down on my way home to hopefully keep from doing any damage. Now, it'll idle/run in the medium range of the gauge, so the coolant is obviously passing through the system.

[wayner123]

Dodge Grand Caravan-it shows the temp gauge in the dash. Prior to replacing the thermostat, it was as high as it would go and one day I even stopped and pulled off several times to cool down on my way home to hopefully keep from doing any damage. Now, it'll idle/run in the medium range of the gauge, so the coolant is obviously passing through the system.

Does it have automatic climate control?

[CasaDooley]

Does Lowe's sell anti-freeze?

:lr That is so wrong and so funny!

[cobra03]

I would check the antifreeze first. My wifes car did the exact same thing last year and it was a combo of to little and to watered down antifreeze. i topped it off with a little straight antifreeze not watered down and it fixed it instantly.

[shark]

It might be a good idea to have the cooling system completely flushed out. Also, maybe have an engine compression check done just to make sure there isn't an issue with a head gasket or cracked/warped cylinder head. Is the water pump working correctly?

[forgop]

Does Lowe's sell anti-freeze?

I'm not going there for it. :r

[hammondc]

I agree it sounds like a thermostat

[forgop]

I would check the antifreeze first. My wifes car did the exact same thing last year and it was a combo of to little and to watered down antifreeze. i topped it off with a little straight antifreeze not watered down and it fixed it instantly.

I hadn't thought of this. I think I've got one of those gauges in my tool box and see what the concentration is.

[tsolomon]

Could have just been a defective part and since it was summer never noticed the heating portion of things.
I had a Ford Explorer where I had to replace the thermostat every year because it wouldn't heat up when the weather turned cold. It didn't make sense, but it worked. :confused:

[forgop]

Actually got around to checking out the coolant level and seems pretty low. Going to do a complete flush and fill tomorrow and see how that works.

[T.G]

I'm not going there for it. :r

:r

[forgop]

I now have heat. I'm guessing my coolant level was quite low. I flushed the system and refilled and it's working now. I guess the thing to watch for is to see if I have a discernible leak in the system somewhere.

[cobra03]

Glad to see its back on track. Hopefully no major leaks.

[kingcobradude]

If it does go bad, a good cigar would warm it up a little

[shark]

I now have heat. I'm guessing my coolant level was quite low. I flushed the system and refilled and it's working now. I guess the thing to watch for is to see if I have a discernible leak in the system somewhere.


Hopefully no internal leaks. Those can be a PITA to track down.

[hammondc]

Did you get some of the UV coolant dye? I have used that before to find leaks.

[thebayratt]

Check the passneger side floorboard. Heatercores are usually in the dash above the floor. If they leak, there will be water on the floor.

Ask me how I know, lol!

[deadrise]

yea I would be scared at this point you just put a thermo in this summer and now low enough on water to produce no heat there is a leak somewhere lets just hope its not the heads

[forgop]

Check the passneger side floorboard. Heatercores are usually in the dash above the floor. If they leak, there will be water on the floor.

Ask me how I know, lol!

There's never been any water leaks inside the van and I've never seen anything underneath the van other than from the A/C running in the summer.

[forgop]

yea I would be scared at this point you just put a thermo in this summer and now low enough on water to produce no heat there is a leak somewhere lets just hope its not the heads

La la la la la....I can't hear you. :D

It's a 2005 Dodge Grand Caravan with the 3.8L in it...

[T.G]

I now have heat. I'm guessing my coolant level was quite low. I flushed the system and refilled and it's working now. I guess the thing to watch for is to see if I have a discernible leak in the system somewhere.

There's never been any water leaks inside the van and I've never seen anything underneath the van other than from the A/C running in the summer.

That means you either messed up big time with the levels when you refilled the system after changing the thermostat, or, you have a slow leak.

If it's the former, shyt happens. Live and learn, happens to all of us at some point.

If it's the latter, a jug of Bar's Stop Leak works wonders. If you really need a miracle, CRC Copper Weld is divination in a bottle.

[forgop]

That means you either messed up big time with the levels when you refilled the system after changing the thermostat, or, you have a slow leak.

If it's the former, shyt happens. Live and learn, happens to all of us at some point.

If it's the latter, a jug of Bar's Stop Leak works wonders. If you really need a miracle, CRC Copper Weld is divination in a bottle.

I've read some reviews that the stop leak type of products out there can also do a lot of harm, so I'm skeptical of using it. That said, I know my wife did get it pretty damn hot over the summer before I got the thermostat. Don't know if it got hot enough to do damage, but I'm not ruling that out by any means.

May put some dye in it and see if that can help me figure out of it's going anywhere. It has ~ $100k miles on it and this thing is gonna be driven until the wheels fall off of it hopefully w/out having to replace an engine or tranny.

[T.G]

I've read some reviews that the stop leak type of products out there can also do a lot of harm, so I'm skeptical of using it. That said, I know my wife did get it pretty damn hot over the summer before I got the thermostat. Don't know if it got hot enough to do damage, but I'm not ruling that out by any means.

May put some dye in it and see if that can help me figure out of it's going anywhere. It has ~ $100k miles on it and this thing is gonna be driven until the wheels fall off of it hopefully w/out having to replace an engine or tranny.

Whatever you say man. I bow down to you your google-foo.

[forgop]

Whatever you say man. I bow down to you your google-foo.

Not disputing what you say, but it just made me unsure of actually using it without getting something other than anonymous opinions.

My guess is that's it's probably similar to what you use in the tire repair in a can stuff. You may seal a leak, but I believe you'll completely void your tire warranty if you do it. :sh

[T.G]

Not even close Duane.

Totally different principles, plus, fix-a-flat doesn't void your warranty. Installing a plug might because in the process of installing a plug, you bend the belt wires in and make the tire unpatchable, but a can of F-A-F doesn't. It's just foamy crap that the tire shop wipes out of the tire with a rag when they go to fix the problem.

Now, tell me what warranty you are trying to protect on a vehicle with 100K + miles? And this after you opened the cooling system and voided it by replacing a thermostat yourself?