If you encounter a vehicle that experiences coolant coming out of the coolant reservoir tank, it may be caused by the radiator cap pressure valve being stuck open by debris sucked up through the reservoir tank hose. As the cooling system cools down, it sucks coolant back into the radiator.

If there is debris that settles to the bottom of the reservoir tank, the hose is low enough to also suck debris back into radiator. This causes the radiator cap not to seal, allowing excessive amount of coolant to escape overflowing the reservoir tank. If this condition continues over time, there will not be enough coolant in the system to maintain proper engine temperature.

In order to correct the condition you need to clean (and test) or replace the radiator cap, clean out the reservoir tank, and slightly shorten the hose, following the below repair procedure.

Chart 1

Affected Vehicles:
• 1999 and later Impreza and Forester;
• 2000 and later Legacy and Outback; and
• 2006 and later Tribeca.

The shorter coolant reservoir tank hose was used in production as shown in Chart 1.

Repair Procedure/Information:

1. Radiator Cap Cleaning: Many caps can be successfully cleaned. The important part ...