Overheating???

[cmm47172]

Hellooooooooooooo.
Anybody want to take a stab at this?
I've seen other posts just like this although they never get to a final fix.
I think most people go online and post questions trying to find a fix for problems and then never post the resolution.
When I find a fix, I will post it so that I may help others. That is provided I find a fix.

[petrified.rabbit]

if the system is actually boiling over at the catch can, the coolant temp sensor will not help that.

if you have actual bubbles in the system, and nothing else is wrong with individual components, and it is over heating, i would guess and lean towards head gasket. that diagnosis involves a compression test, checking your your level is not climbing, and smoke or moisture coming from the exhaust tip.

[cmm47172]

The temp gauge reads normal. the car runs perfect. No water out the tailpipe. I would guess the head gasket is fine. One thing I do know is that the fan never comes on even if I turn on the air conditioner. What would cause that?

[thankful_ragamuffin]

As Service Manager at the local Napa Autopro shop, this is how our techs would approach the diagnosis based on the symptoms you have given: 1) Engine cold, ignition off, spin the cooling fan to see if it turns. If it doesn't turn, the fan motor is pooched. There should be a fuse blown for that circuit as well. If the fan turns and the fuse is good, they would use a scan tool to command the fan on. If the fan can be commanded on by the scan tool but the A/C doesn't command it on they would look for a communication error with the ECM/PCM. 2) Engine warm, after a test drive, would use a laser thermometer to match actual coolant temperature with gauge (or scan tool). A candy thermometer could sub in for a do-it-yourselfer. Operating temp should be around 195F. 3) Check for presence of carbon monoxide in coolant (there are kits available for this). If present, head gasket is pooched. If bubbles are present in normal temp coolant, head gasket is pooched. If the heat fluctuates in the heater, head gasket is likely pooched. Unfortunately, excess pressure in the coolant jug usually equals head gasket is pooched. Let me know what you find.

[cmm47172]

I fixed it!!!!!!!!!
So I was reaching my wits end with this problem when I decided to give up and go to the dealer for a good shellacking and let them fix it.
As I pulled up to the dealer service door, I decided to leave the car running and pop the hood one last time in an effort to see what was happening before I turned it over to the service guy who was opening the bay door so he could come out and relieve me of my wallet.
When I opened the hood, I could see there was a pin sized hole in the side of the plastic “pipe” tubing that runs from the thermostat housing to the throttle body. With the engine running I could see coolant peeing about 2 feet thru the air and landing right on top of the catch tank!
At that point, the service guy asked if I wanted to pull in for a repair and I said "No Thanks! I'll keep my money and fix it myself!" I did let him sell me the replacement part (around $35.00) and then I was on my way back home, happy that I could fix it myself and save $$ in the process. When I got home, I gently squeezed the line and it shatter like glass. The entire length of the line was very brittle. I replaced the line and now it is fixed! I should go ahead and replace the other plastic pipe that runs from the throttle body back to the catch tank however; I decided to hold off on that until the weather warms up a little bit.
It looks like we all over thought this issue although I blame myself for steering everyone in the wrong direction. When I initially saw coolant on the catch tank, I assumed the pressure cap was releasing coolant because this was the only area on the engine that I saw the presence of coolant. In hind sight, I should have done two things. First, I should have inspected the problem with the engine running. If I had done so, I would have immediately spotted the problem. Second, rather than visually inspecting coolant lines, I should have grabbed it firmly with my hand to see if there was any movement. Doing so would have broken the line into little shards thus exposing the issue.
Since the fix, I spoke with another 2009 Aveo owner who said that he was having the same sort of problem. I told him to check the tubing and when he did, he saw the line was brittle and leaking as well.
I would like to seriously say Thanks to petrified.rabbit and others who attempted to help me with this issue! You guys are awesome! I hope this post will help others in the future. I would also like to “sarcastically” say thanks to Chevrolet for using such crappy material when making parts. Doing so helped me to spend unnecessary hard earned money and take boat loads of precious time out of my life trying to fix the dad blame thing. Go Chevy!

[avguy]

Thanks for following up and posting your resolution - this will certainly help others down the road