It isn't on my SS, its on my dodge stratus. This is long, but I want to make sure the situation is clear. I am asking here because the dodge boards aren't as technical as LS1tech. I am hoping someone here might have an idea what is going on. If I shouldn't post this here, please move it to the correct location.

The last 2 weeks, the stratus has been pushing out the radiator drain plug enough to open it up and drain the radiator. The plug isn't the normal screw in type, it is one that you push in, turn left and then it pops out enough to drain the radiator.

So I put a new plug in thinking it was broke or didn't catch anymore. So I install the new plug and fill up the radiator and all is well. I put my funnel in place of the cap and turn the car on. Once the car starts, it is violently pushing water/coolant out of the funnel. That has never happened before which worries me. (head gasket?)

Ok, no biggie. I turn the car off and let things settle. Come back and fill the radiator up, start the car and go for a test drive. I drive around a while in the local area and stop to put gas in the car. As soon as I do, I see a puff of white smoke coming out of the engine bay. Oh crap, off I go to the house.

Come home, park it and crawl under the car to make sure the plug is still there and it is completely gone. Crap. Still have the original (which looks perfectly fine).

The radiator was replaced at 140k miles and the timing belt/water pump combo at 167k miles. The car has just a few miles shy of 175k miles on it now. Could the head gasket be going? I never noticed it getting warm, much less hot before (maybe the stock gauge is shot?) When I was adding water/coolant in the system this time with it splashing like it was through the funnel, has me a bit worried. Tomorrow AM, I will check the oil to see if it is milky (dark out right now w/o lights near by).

Sorry this was so long, I just wanted to give a good background on the car. Anyone have any ideas why the cooling system keeps popping the radiator drain plug out (or out enough to drain it)? The violent nature of the coolant shooting out everywhere from the funnel with the motor running has me worried. Like I said, it never did that before.

Thanks in advance.

 

A compression test comes to mind........

 

Sounds like the cooling system is getting over pressurized. Try a cap first, but if its doing it that fast, it sounds like a head gasket. Compression and leakdown test would be a good idea.

 

Thanks guys, I was afraid of that.

 

If anyone wanted to know, I checked the oil. Perfectly normal. No signs of coolant mixing and smells just like oil without the sweet coolant smell. Compression/leak test here I come.

 

I have an 02 stratus and just had it completely checked out in anticipation of sending the car with my daughter to college. One of the things that had to be replaced was a steel coolant tube that ran between the engine and firewall. It was both heavily corroded and clogged. The thermostat also had to be replaced because it was seized fully open. I imagine a seized closed thermostat might cause the symptoms you are experiencing. The coolant pipe, unfortunately, is a dealer-only item, unless you luck into one at the boneyard.