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Can't figure out the problem

I have a 2001 chevy venture van. I cant figure out the problem.
Driving to work its cold as hell in my van so i know there is something wrong with the cooling system.
The next day my temp gauge was fluctuating tremendously (its -20 degrees celcius where i live right now). normally i let it warm up for about 8-10 minutes before driving it then it is warm fairly quickly. I checked my overflow reservoir because i new i had a small leak in either the hose leading to the rad or in the rad itself. But based on how little actually leaked out and in summer it stops leaking I wasn’t too worried about it. I tried throwing in some stop leak just for safe measures. I had to pull over while driving home because my thermostat gauge was skyrocketing super high an the van would take the accelerator away from me, keep in mind it overheated doing about 60km/h (37mph) down the road. I pulled over and looked at my overflow tank and all of the engines coolant was in there and when I opened it initially it started pouring the extra coolant on the ground. I thought it was odd but maybe i just put too much in and continued after draining some. Then it refused to do any faster than 60km/h and kept limping and taking my accelerator away. I ended up getting it home after a few hours of stop and go. I know its bad to drive with no coolant but it wasn’t worth towing.

Trying to figure out why there is no coolant being pumped either back into the rad then the engine or why its not just going back into the engine at all.

Sidenote, not the most intelligent when it comes to fixing cars.

From what you stated about the problem it seems to me that the engine has a head gasket problem and combustion gases are getting into the coolant. If that is the case you will need to at least replace the head gaskets.

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You probably have a blown head gasket. The engine may now be ruined. Take it to a good mechanic to determine if it’s worth fixing.

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Ask your shop to check the freeze protection temperature for the coolant. Sometimes during the summer a shop or owner will pour plain water into the coolant to top off the cooling system, and that raises the freezing point, but it doesn’t show up as a problem until winter when slush starts to form in the cooling system.

As to the disappearing coolant . . . there is a very good chance the lower intake gaskets are shot, allowing coolant to go into the crankcase

That would explain the disappearing coolant AND quite possibly the overheating

I’m saying this because your van uses an engine that is known for the problem I described

It’s not odd that it poured on the ground

That’s normal, because the system was hot and pressurized

Be thankful you didn’t get a faceful of hot coolant vapors

You could have gotten seriously burnt

Don’t ever make that mistake . . . unless you actually want to get burnt and/or lose some

What’s the overall condition of the van?

Are you planning on doing these repairs yourself

If the overall condition is only so-so AND you have to pay a shop for the repairs, it might not make any financial sense to try saving the vehicle . . .

I’m saying this because a 2001 Chevy Venture isn’t worth much

If you have a known coolant leak, the coolant loss alone can cause overheating, Also, any leak will cause the coolant not to drain back into the engine because it causes lack of the vacuum that draws it back in.

There is no such thing as too much coolant in the cooling system, you can overfill a recovery tand but it will just push the extra coolant out onto the ground when the car warms up.

Hope you have not damaged the engine by overheating it but that has to be determined by a mechanic at this point.

There was some water put in during summer, but it was taken out before leading into winter. The engine is fine and runs normally. There are no odd noises etc. My guess was that a minor leak may have gotten worse preventing it from creating a negative pressure to suck the coolant back into the system.

DB4690, its not that its disappearing, its that instead of being pumped back into the rad then back into the engine its just all in the overflow tank. when i opened the overflow tank the coolant was cold, it couldn’t have possibly been hot as the vehicle never got to the point where it could have warmed the coolant. I do know never to open the coolant reservoir unless the vehicle is cold as it has hot ass coolant in it. Also I forgot to mention the constant variation in my temperature gauge going from almost overheating to almost completely cold. From that I assumed air was getting into the lines and also sometimes bringing coolant with it.

As well when I drove it back home, I would pour coolant that i had into the reservoir while it was hot because I knew there was no coolant in it. I would completely let the engine cool, which was quick being how cold it was outside. I would drive it to the next range road, pull over and let it cool again and pour more coolant in. The stretches of driving were no more than 5-6 minutes. Only about 30 seconds of which was it over heated. But i did repeat that process about 5 times.

Also I couldn’t get at the leak to fix it as where the hose ran, so I tried using a stop leak product, not sure which one it is as of this moment. But after which it was working fine. Then “died” 3 days later

I think if you have the coolant “sniffed” for exhaust gases getting inside it, you will have an answer to ‘one of life’s persistant questions’.