This isn't a hunduh but I think it should still be the same ----. Wife's 01 chevy venture is having a problem. The temp guage is fluctuating along with heat from the vents. I installed a new thermostat and it's still doing it. Yesterday it overheated on me while on the highway to work when I cranked the heat thinking it should of helped it out but made it worse. I pulled over and shut it off before it got bad. Let it sit for a few minutes. Started it back up and turned off the heat and it was fine the rest of the way to work. Drove home from work with the heater off and got up to half and would just fluctuate between the first mark above cold and halfway.
So I just spent the past two hours changing the thermostat and it didn't do a damn thing. I checked the oil to see if it was milky like the headgasket is leaking and no dice. Coolant looks fine as it has that goofy red dex-cron ----. It was milky looking under the oil cap but it's mostly from condensation from what I'm told. I'm baffled and don't want this thing overheating or leaving her stranded with our kids with this nasty winter were having in the midwest. HELP!!! Would air in the cooling system cause this? Once it cools down I'll try bleeding it again and see if that helps.

 

like if there's any air bubbles trapped in the coolant somewhere. It's weird why it fluctuates back and forth so much. I mean if it was the water pump either it'd leak or just overheat. I could be driving it and the temp needle can bottom out by the cold side.

 

Sounds to me like the head gasket it leaking exhaust into the coolant.

Do a compression test, or a leakdown to see where the leak is for sure.

Milky oil is a sign you have a VERY blown head gasket. In most cases, it won't happen with the blown HG.

 

It looks kinda low so I'm hoping it's just that cause the engine is a nightmare to work on. It's stuff in the back with half of it only reachable. If it's the headgasket I'm gonna tell her to take it to a shop cause I don't want to touch it. Hell changing the thermostat took 2 hours and I sold my lift a couple of months ago.

 

Are your fans kicking in correctly? Also if the coolant hasnt been replaced by you I would switch to redline waterwetter. I couldnt imagine a blown headgasket has I dont think any companies still use the old paper style gaskets. Metal headgaskets on stock motors can take some serious beatings before any problems occur.

 

Isn't redline not recommended for areas that go below freezing as it can crack blocks because it can freeze? I don't want to say it's the headgaskets as it doesn't leak coolant so it kinda narrows it down to the headgaskets. The fans do kick on as I thought it could just be the coolant temp sensor but after doing some searching these beasts have alot of issues with the coolant systems and headgaskets that GM are turning their heads away from. Maybe time to tell the wife to trade it in and find a different minivan. Odyssey FTW!

 

Or a toyota. I have no idea regrading the waterwetter in cold places I live on the west coast.I say trade it in man and get a jap car before it gets to bad and the dealer will low ball the **** out of you.

 

common problem....lower intake gaskets...check for it and let us know.

 

I was telling the wife it's time to trade it in. I was doing some more searching and noticed the intake manifold gaskets mentioned also. Man the thing isn't even over 90k and only seven years old. Gotta love GM quality. This just had to happen after we spent all of our tax returns paying off bills.