2011 Aveo overheating, blowing out coolant

[avguy]

… I will need to get it tested/or emptied and filled with all anti freeze for winter. ….

That's something you could DIY for less than a shop would charge, and it wouldn't be all that much work either. Just buy a tester like one below, along with an inexpensive fluid pump, and find out what the current coolant protection is. Then, assuming it needs to be improved, pump out the overflow tank contents. Then refill the tank with concentrated coolant, run for a day or so to fully remix the system, then test the coolant again. Just continue doing that until the protection is back to where it needs to be - probably not more than 2-3 reps would be needed to get it back to 50-50.


https://www.amazon.com/Performance-T...9611380&sr=8-4

[MuteMarmoset]

I will certainly do that once the dust settles.

I drove the car to town today. After burping the system and putting in coolant, it seemed to be running really well. No trouble getting there, then I stopped to drop something off. When I started again it overheated in less than 3/4 of a mile. I called the mechanic I was heading for anyway, and he told me to let it cool for a half hour. I opened the hood and it was so hot I could barely touch the support rod.

After a half hour, it started up again fine, and I drove to the garage, which was perhaps 4 miles away. It would be my luck that his diagnostic tool was acting up, but the code for the check engine light did indicate a cooling problem. He opened the hood to listen to it and we stood there talking about what had been done so far. That's when we could both hear a change in the running sound. He stuck his hand inside the front and found the cooling fan was not working.

I'm not technical enough to explain the entire process but he used a little plug in device that would relay around the fan to see if it was actually functional, and it was. Then he got under the car and what he found, was that the contacts for the fan were corroded and covered in gunk. He said the reason that the acting up was so spotty, was that out on the highway it's a smooth run and continuous working, but when you stop and start like running errands in town, it was more likely to stick and stop working. Then he asked if the AC was working well.

Back in June after the first time it boiled over, I discovered my AC wasn't working and it turned out I needed freon. Both my own mechanic and the one where I took it for that work told me that the AC had nothing to do with the overheating, which was wrong. If the fan is not working right, you're not going to get the cool air in, nor cool air over the engine. And there were times that it seemed not to be putting out enough cold air and I put it down to our unusually hot summer.

Bottom line (for now): He cleaned the contacts off and everything looked good. I was able to drive around town on errands, and then the 25 miles home with no issues. He said it should be fine, but it it happens again, I would likely need a new cooling fan.

[Houdoxi71]

About 10 years ago I bought a 2001 Audi A4 Avant 2.8-6 from a small used car dealer for almost nothing, due to the fact that it would puke coolant out and they didn't want to fix it. Turns out the timing belt was incredibly loose and essentially wasn't engaging the water pump at low engine speeds. That particular car also had an aux factory installed electric water pump, for emergencies/parked too hot incidents. Naturally, it didn't work either, and the heat from the iron block (being trapped with no actual coolant flow) would "boil over" the overflow tank in traffic, or when parked hot.

A 2011 shouldn't have a timing belt driven pump, but that doesn't mean the pump is still working like it should, or some blockage is preventing it from pushing the correct amount of coolant thru the system.

Hopefully it is just the fan, after all. The ac condenser sits in front of the radiator, so all of the exchanged heat goes right into/past the radiator, and without the fan the coolant will get too hot and expand past the capacity of the system.

[MuteMarmoset]

Thanks for the input.

I have been testing the fix. I drove around town then home with no problem. Then I let it sit three days before taking it out for a couple of short drives, and it was still good. I have since been to town and back twice, and it's still not overheating, so I'll likely bite the bullet and head to the city this weekend which is about 110 miles round trip.

I don't know as I'll ever fully be confident in the car again, as the first time this happened was June, then it didn't do it again for over two months. But at least now I have a pretty good idea of how to deal with it.