2000 Mercedes Benz E320

So here is a quick rundown of what exactly has happened within the last 2 days. While driving a couple days ago, I started to hear a sound that could almost be described as the sound of air escaping some sort of pressurized area from the bottom of my car. After parking at home, I left the car in idle, the popped the hood open to see if anything was open/leaking; I noticed that there was now some water that was leaking out of the bottom of the car. Additionally, when I’m not driving on the highway (for example, residential roads, etc.), the engine temperature run up almost 10 degrees Celsius hotter than usual. I checked the engine cooling system to see if that was leaking, but that is still full to the brim. Any ideas? I have next to no expertise in cars and troubleshooting issues them, so I’m turning to the internet for help.

You have a coolant leak. It’s probably a pinhole leak in a hose somewhere. These cause a pressure drop which reduces the cooling efficiency of the system and causes it to run hot, but they don’t lose all that much coolant over a short period of time, so you might not notice the difference just by looking at the reservoir.

Your car is old enough that if it’s on its original hoses, it’s very likely that they’re worn and need to be replaced.

Myself, I’m kind of leaning towards water pump and/or radiator

This has a plastic/aluminum radiator, and if it’s still the original, it’s on borrowed

In any case, any decent mechanic should be able to quickly figure this out. Better yet if he has the proper adapters to perform a coolant pressure test

Water leaking… with a pressure sound…sounds to me like the A/C was on… Coupled with the fact that the cooling system was full with no visible leaks.

Hard to see from my computer over here tho…

Blackbird