I come once again to beg the help of the Dodge Jedi masters. Last time, y’all helped me with a maddening electrical problem, so I’m hoping you can do it again. This time it’s the cooling system.

I’ve searched the forum and found nothing that seemed relevant, so I’m posting. I’m gonna give all the details, just in case they’re important.

The car is a ’97 Grand Voyager SE with the 3.3 V6 and A/C, 245K miles. About 3 weeks ago, I noticed it was taking a long time to get heat in the cabin. The problem got worse, but it didn’t occur to me to check the coolant level until finally the (usually rock-steady) temp gauge abruptly rose.

Sure enough, the coolant level was low. I figured I had a leak somewhere or a failing water pump. I filled it with water temporarily (I know, I know) until I could pinpoint the source of the coolant loss.

So after that, I’m driving around with water in the cooling system, I’ve got heat, and I figure I’m gonna have to replace a water pump over the weekend (I’ve done one on every Caravan I’ve owned).

Then, at work last week (I’m a pizza guy, meaning I’m poor and I drive crappy cars), I had no heat again. I figure that means I’m dry again, so I top off. It took about a gallon in the radiator with the engine running, which didn’t seem like that much, but what do I know?

At this point, I started topping off the radiator (engine running) every other day before I drive the car, but each time it only takes about 12 ounces.

Today I drive around for about 20 minutes and no heat. I figure I’m dry again. The car is warm, but according to the gauge, not hot. Using the time-honored hillbilly bath-towel technique, I open the hot radiator (I know, I know) and a fair amount of rusty water burps out, but it doesn’t seem like it’s overheated. With the engine running, I fill it with a hose. Water burps out occasionally, then the level drops and I can add more water. Maybe this is normal?

Anyway, I did this until I was pretty damn sure that the cooling system was full. Maybe it was full before, I don’t freakin’ know. I capped it, and within 5 or 10 minutes I saw some steam coming out from under the cap. Later inspection showed no obvious problems with the cap’s rubber seal, but as I said, what do I know?

Now, at this moment, I have what I believe to be a full cooling system and zero heat in the cabin.

So: if it’s the heater core, why am I losing coolant? And if it’s a leak (from the water pump or someplace else), why do I have no heat?

Except for that first time, the temp gauge has stayed right where it belongs throughout this whole ordeal.

Possibly irrelevant details: The heat and a/c blower fan has always had an occasional squeak. Recently it’s been squealing a lot. It still runs, though. But when you turn it completely off, a “flapping” noise comes from that general vicinity, like a plastic vent door is flapping open and shut. I had a look around in there last week, but I couldn’t see anything.

This is an $800 car. But it’s MY $800 car, and I wouldn’t mind getting a few more miles out of it! Any thoughts?

 

Sounds like a head gasket or cracked block. Check to see if your oil level is discolored or getting higher or if your exhaust smells funny.
As much as you have added if it was going into the oil it would have shut down by now.
Its possible perhaps a heater core line is ruptured and its going under the carpet undetected but the smell?

 

I'd be looking at a clogged cooling system/heater core before I'd look a head gaskets/engine problems. Only problem is that if you DO manage to flush it all out, you are almost guaranteed to need a new heatercore and radiator.

 

Well, it turns out that the water pump failed. In fact, it had failed so spectacularly that by the time I was done filling the radiator, checking the temp gauge, and waiting for heat, ALL the water had leaked out. That's why I didn't see a drip—by the time I got around to looking, it was all gone.

In my defense, I don't have a garage, so I was working outside on the street on a rainy day—the leaking water must have mixed unnoticed with what was already running in the gutter. And since it was just water, it wasn't green!

That said, I still feel like a total chump. Thanks to everyone who tried to help me, but I may be beyond help. This small animation sums up my feelings on the subject:

 

Here is how I found my water pump, do yourself a favor and make sure one with plastic impeller is not installed.