What could be wrong?
Hummer Q&AAsk Your Question
2003 Hummer H2 Question: Low coolant light comes on. Just added coolant last week. No signs of leaking
Answer #1Tyreguy November 04, 2011, 12:13Master
Keep an eye on your coolant level. If it continues to loose coolant, and there is no evidence of external leakage, have the system pressure tested. Its possible the engine has developed and internal leak and the coolant may be leaking into a cylinder, or the oiling system (pan/galley).