Model : SUBARU 2002-2007 WRX /2004-2018 STI WRX/STI. Make : SUBARU. Your cooling system was holding used coolant. After the new radiator has been installed your entire. CONTAMINATION AND ADDITIVES: Contamination and additives can clog passages and reduce overall heat transfer.Pure coolant liquid or mixing different types of liquids will also cause sludging in the system.
