That is either a hole to hold the rubber internal seal or a small bleed hole. Either way it will not cause an external leak.

 

@02 LW300

The gasket kit didn't come with the gasthe/o-ring that goes between the thermostat housing and cylinder head. This sucks. It was hell finally getting the pump off and now I'm hoping I don't get a leak reusing the gasket in that area. I overlooked your suggestion to get a thermostat gasket kit. I thought the one you suggested had everything! 😭😭😭

 

If you mean the 'formed' gasket that's in the groove in the thermostat housing, the 'o-ring' that has a square cross section should be in that kit. You shape it while inserting it into that groove. The squareness keeps it in place while you mount it to the engine - a round one wouldn't stay in place.

 

My mistake. I forgot I went with [this one](https://a.co/d/4WPmbuk)

So using a circular one wouldn't work? That's all there was other than the two big water pump ones. No rectangle ones like the one in the thermostat housing. Think it's a bad idea to reuse the old one? I don't have another choice at the moment

 

The o-ring in the kit is shaped like a circle, but the cross section (if you cut through it with a knife) is square/rectangular. It will fit into the groove on the housing. See this YouTube video at 8:00. (This is the thermostat housing from a newer ecotec engine with the thermostat on the top side.)

 

WOW! 😭 I wish I had known that. And I almost used a round one thinking it was the right part, but I didn't want to remove the old one and be wrong. For some reason, I was extremely difficult to line all three thermostat housing bolts up. Once I got one in, one of the other two was super difficult to turn, and the other wouldn't line up. No matter which one I put first. Finally got em lined up, but I thought i stripped the since it was a tight space, and i could only turn so much at a time. Also, the plastic part of the temp sensor cracked into two pieces smh. Had to use some devcon aluminum putty to put it back together. It's all I had. Hopefully, it holds.

I've been at this for more than 24 hours straight. Small issues one after another kept popping up. Had to remove the brake fluid reservoir, fuse box, the metal rack the fuse box sits on, the computer. Man, this was a tough one. Putting everything back together. I really don't wanna try and mess with that thermostat housing again. I wish I'd seen your answer before I finally got it on. You think it's a big risk tying to use the old gasket there?

​​​​​​​Thanks

 

If the original gasket showed no damage and wasn't hard as a rock, you're probably okay. The cooling system operates at only 15 psi, and there's almost no exposure of the gasket to the coolant in that place. Congratulations on getting that job completed! That's a hard place to work on in that car.

 

Thanks It was horrible! On top of that, strange things are happening.

1. I get the code p0016. Google says it has something to do with the timing 🤦‍♂️

2. The engine seems to be overheating. I don't see any coolant leaking anymore, so far. I wonder if this has anything to do with the temp sensor. The aluminum putty didn't hold up. I still tried to apply a second pass, but i think it was weaker than the first pass. I screwed the bolt half in the head, inserted the connector into the other half that's just a plastic piece, then I just pushed kt firmly against the bolt half and it's somehow staying in place. Not sure of the connection. But Google says this can cause overheating. Is that true? Hopefully, it's just a misreading, if anything.

3. Oddly, my blower motor only works on levels 1 and 2. Don't know what that's about, or what could have caused this

4. This one was kinda obvious, but smoke was coming from in between the head and firewall. Almost looked like it was coming from a coil. My guess is that it's spilled coolant from draining from multiple spots onto the engine and anything else that gets hot when the engine is running.

I was excited and proud to have gotten this task done. Now I'm just pissed stressed, and tired. Any tips would be great.

Thanks

 

I think you're right, that it's the temperature sensor. I'm not familiar with aluminum putty, but if it contains aluminum it may be affecting the electrical signal the sensor is sending to the ECM. When you say the engine is overheating, are you referring to the temperature shown on the water temperature gauge? This would certainly point to the temperature sensor. Smoke (steam?) coming from the area where you worked is probably coolant and old grease or grime burning off the exhaust manifold. It should clear up after running it for a little bit.

On the P0016, that is a crankshaft/camshaft correlation error. The ECM thinks there may be a timing issue. But on this engine (2.2L) there is no camshaft position sensor, so the ECM has no signal to compare. I seem to remember reading that the P0016 code may mean something else, but do not remember what that is. In any case, replace the temperature sensor, clear the codes, and see if it resolves itself.

 

When starting after a cold soak, when do the cooling fans by the radiator under the hood kick in? At what dash gauge reading?

Agree with above advice re: replacing temp sensor.