too much pressure in the coolant system? - United Bimmer Community

**ntroisi84** · 04-03-2010, 09:34 AM

Hello all,

I drive a 96 328i. Last week I went into a store and left it running. When I came out the temp was in the red. I let it cool down and drove it home. I changed the thermostat and it was fine for about a week. Last night I was driving and I heard a pop. All of the coolant sprayed over the road. I am about to throw it up on a jack to identify the leak. It seems to be coming from underneath the back of the engine. If anyone has any suggestions what it might be from, it would be a great help. But I noticed that coolant leaked from around the cap and there are traces around some of the hoses on the radiator, like the coolant was pressurized to much. There is also a little black cap floating in the resevoir. Does anyone know what this is, and is there something that could cause the system to pressurize to much? I checked the oil and there are no traces of coolant in it, so hopefully it is not the HG. I have heard that overheating it once can cause it to blow.

**ntroisi84** · 04-03-2010, 02:46 PM

Well just finished fixing the car. It was a hose going from the back of the engine(cylnder head?) to the heater valve. It was the hardest hose I have ever replaced. There is just little to no room to get to it. I took some pictures of the process I used and will post them soon if it will help anyone. But if anyone knows why there seems to be to much pressure building up, please let me know.