Coolant leak, not sure where

Knn04Z4

Member
 Virginia
Recently bought a beater 04 3.0i. Loving it so far, but starting to see why I got it for so cheap!

I've had to top off the coolant 2 times since i've had it for 6 weeks. First time I wasn't so suspicious because the guy I bought it from barely drove it. This time I noticed coolant on the garage floor...

I recently drove it about 50 miles and the next day notice the puddle on the ground

It's on the panel below the engine and even on some parts of the engine pulled up. I'm hoping it's the water pump but based on what I'm reading it could possibly be the head gasket... If that's the case I'm going to have to make a hard decision 😭

Got the best pictures I could. She's got 200k on the clock and a stack of dealership service notes from the 2 previous owners. They replaced the water pump around 130k
 

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Check the temp sensor in the hose to the thermostat. The o-ring seal can leak onto the belts and fire coolant all over. Also the top hose where it meets the thermostat. The seal inside can flatten out. Give it a wiggle and see if anything leaks out. Failing that, water pump or the seal between the thermostat and the head
 
That's for the replies! I have noticed that it leaks more when I drive highway speeds then just around town, and I've been reading and watching online that can be an indicator of a failing water pump. i felt around the thermo housing and it wasn't wet or had visable signs of coolant. Not did the tubes from first glance.

In the pictures it's hard to tell but there is a puddle build up on the floor of the engine bay and coolant all over the outside of the engine towards the bottom right. Also pictured but blurry
 
That's for the replies! I have noticed that it leaks more when I drive highway speeds then just around town, and I've been reading and watching online that can be an indicator of a failing water pump. i felt around the thermo housing and it wasn't wet or had visable signs of coolant. Not did the tubes from first glance.

In the pictures it's hard to tell but there is a puddle build up on the floor of the engine bay and coolant all over the outside of the engine towards the bottom right. Also pictured but blurry
Do you mean bottom right, as viewed looking backwards?
Underneath the expansion tank?
They are well known for splitting, or for the seal at the bottom failing.
 
Do you mean bottom right, as viewed looking backwards?
Underneath the expansion tank?
They are well known for splitting, or for the seal at the bottom failing.
If you're looking at the front of the car, the space between the air intake and the engine. I looked down through that and noticed the engine block had coolant on it

I don't think it's the expansion tank due to where the coolant is on the engine
 
If you're looking at the front of the car, the space between the air intake and the engine. I looked down through that and noticed the engine block had coolant on it

I don't think it's the expansion tank due to where the coolant is on the engine
OK, could be running down the belts and dripping off the pulleys on that side then.
 
After some further research, it is most likely the water pipes located under the intake manifold. Seems to be common for the high mileage M54s. Curious how much it'll be 🙃
 
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