Car has 90k on it and is very clean. recently it started leaving anitfreeze puddles in the driveway. They are a couple ounces, not a flood. I have looked under it as well as my mechanic and the head gaskets are dry. Water pump is dry(weephole clean). We put a pressure test on it for over an hour at 15psi and NOTHING, not a drip. There are stains in the rear on the bottom of the bellhousing and front of the pan. It looks as if it may have a leak behind the bellhousing like a freeze plug or something. The rest of the freeze plugs look literally brand new. The car only puddles about 2-3 times a week and it puddles in the rear of the engine kinda on the driver's side.

Funny thing is this: It only does it when it is hot like after a 1/2 hour run+. I did one last night and parked it. 2 hours later I came out and the driveway was dry. This morning I have a puddle. What gives? Seems like it only happens after it cools for some hours, etc. Is there a place in the rear of the block to leak from? Are there any hoses or senders that are back there that could leak? What could leak spiratically like that?

Also It is my wife's car so I don't drive it very often. The temp needle is about 80 on the highway and creeps up close to the 100 mark in traffic. Is this normal? That is where my 560SEC ran but not sure about this E420.

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