Water overflow from reservor - 2006 Chrysler Sebring 2.7

If the coolant level in your reserve tank seems to be going up, instead of down, you may need to check for a leaking head gasket or intake manifold gasket. Escaping exhaust gas from the combustion process will send bubbles into your coolant, expanding it to more than system capacity. This will also cause engine problems pretty quickly, too.

If your concern is that there's a puddle of coolant under your car after you've parked it, another problem could be a cracked reservoir. These are essentially large plastic jugs, and they're exposed to a lot of heating up / cooling down cycles. Replacing a cracked coolant reservoir is dramatically cheaper than having engine work done, so I hope that's your problem.

Good luck.

Change the cap