So today, I was sitting in my car listening to Lebron talk about how he will be playing for Miami next season. The moment he said he would be going to South Beach, I heard a loud pop sound from the engine and subsequently saw a lot of steam come up from under the hood. I immediately popped the hood open and saw fluid splattered on the engine block (passenger side) and coolant pouring out underneath the car. It wasnt anywhere near the radiator. Passenger side, halfway back. It was definitely coolant, the smell made it obvious.

I have no idea how this could have happened. The car is an 06 550i. Do hoses deteriorate after 4 years? The pop sound leads me to believe a hose burst. Could it have been that I was running the AC while the car was on, yet not moving? Anyone familiar with the layout of the engine and components? Are there hoses in that general area that carry coolant?

Any advice would help. I'll try to put a pic up and point out where coolant leaked from.

Thanks!

* Something tells me Lebron going to Miami is a bad idea lol! Go Chicago!!!

 

If its coming from the passenger side it sounds like it could be the coolant expansion tank. Since its made of plastic it will deteriorate over time, but check the hoses too.

 

It could be a heater core hose

 

I had a similar thing happen to me... my expantion tank blew apart at the seam while I was in heavy traffic. It made a pop and steam came out from under the hood. No problem though, just replaced the tank and all was well. Scary though... Good luck.

 

I've never had this happen but the expansion tank theory is likely the correct one here.

I don't think, even though it's made of plastic, that deterioration of the material is the culprit. It's more likely that the tank burst at it's seam (as 545 Guy suggests) due to a defect and due to the pressure from the system.

 

Thanks everyone! I will find out tomorrow from the dealer. Now that I think about it, the popping sound does sound like a plastic tank coming apart.

 

this is such a common problem...happened to me too. First time it was the hoses that need to be replace, then the box needed to be also replaced because it melts inside after sometime..

 

this exact same thing happened to me. it took 2 visits to the dealership to take care of the problem.

 

These things were popping like mad on the e46's, I had one go out as well. PLASTIC, Brittle and under pressure. Go figure.

 

You guys were right...Dealer just called. It was the plastic tank!