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Coolant expansion tank overflow/ bleed off location? Head gasket?!

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Where does the overflow tube dump? I've been experiencing a coolant leak (intermediatly not constant) from the right passenger wheel well (behind the wheel well(engine side)) and am trying to diagnose it. Seems to dump about a quarter to half a liter after I park the car. Ideas are as follows

A. Head gasket (don't know about the likelihood of that but any things possible)

B. Fracture in expansion tank

c. Loose connection to/from expansion tank


At this point I'm pretty sure the coolant pipes under the manifold are not involved. I cannot locate the leak from the top only the bottom see pictures. Possibly there is a loose connection under the CET and the fluid is running along the tube somewhere I can't see it??? Seems to leak only when the engine is up to temp and parked or stopped (in idle or off)... Any ideas? The engine has not been overheating as it is infrequently driven (20 miles per week) and kept under a sharp eye since this problem has come up.

The reason I said head gasket is because after a 15 minute drive today I parked the car ( with engine running in idle) and took off the fill cap after releasing pressure. I noticed the coolant was very high and slowly rising! Just before it overflowed an air bubble came up and the coolant level dropped by about 1 inch... However it was still far above the max line.

Aware of the leak I checked it before the drive (engine cold) and added about 1L of fluid to bring the level back up to just below the "max" line.

Could a blow head gasket force air into the coolant system, BUT NOT show water in the oil? I don't see any noticeable performance difference,nor any symptoms of a blown HG... Wtf man...

The coolan can be seen dripping from the area around the silver bolt within the suspension and falling around the front right passenger wheel spindle.


Edited by thatguynikko
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here is a short video I just took explaining symptoms im having








I see nothing unusual in that video; the coolant in the tank appears to be expanding as it heats up - completely normal.  Water vapor from the exhaust - again normal in cool or cold weather.  If you had coolant entering the exhaust system, you would not be able to see the rear of the vehicle for the steam (a couple of drops of water makes gallons of steam).


Porsche uses a MLS style head gasket that is actually stronger than the engine castings, which is why they never fail.  Normally, when a Porsche starts leaking coolant into the combustion chambers, something has cracked.

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