Lift up the carpet in the rear trunk and see if there is water underneath it. The carpet itself may not be wet because there is a cardboard panel underneath it. If its wet there the bottle is leaking.
If you undo the nuts that hold the bottle in sometimes you can pull it out enough to get to the hose clamps. Also replace all the hoses while you are in there otherwise you will be doing it again.
I was always scared about RMS leaks... now I have a coolant leak from hell!
Last week I paid $900 for a new Coolant Bottle, because of a leak in the trunk
and under the car on the right passenger side. This week The coolant leak
has started from the middle of the car on the left side.... I guess I'm in for another BIG repair bill.
Wow, $900 for a new reservoir. Did you take it to a dealer? I paid right around $200 for a new tank and cap and did it myself. $700 tacked on to that for labor seems excessive.
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2000 Boxster.
1997 Carrera 993.