Reader Question: I am losing coolant in my 1997 Chevrolet Lumina 3.1L engine. We cannot figure out where it is all going can u give me some tips on what to look.
I took it to a mechanic and Jiffy Lube this morning because my coolant light came on, no one can find the leak. Where is the black hole? Please help!
I would find another mechanic and get a cooling system pressure test. This is a simple and inexpensive test to located coolant leaks. If you are continually adding coolant to the radiator…not just the plastic overflow bottle on the side of the engine, then you probably DO have a coolant leak either external like from a leaking radiator hose or an internal leak like from a head gasket.
Make sure the mechanic also tests the radiator cap itself with the pressure tester.
Here is a similar question about head gaskets and what happens when there is a problem with them.
There are quite a few heater hoses on this engine. Therefore, the likelihood that your leak is from a small rubber hose at the back of the engine is very probable. If the mechanic is not taking his time to properly pressure test and inspect ALL parts of the cooling system, they are likely to overlook a small seep at a hose connection or something hidden towards the back of the engine. It is common for me to leave the pressure tester hooked up to the radiator for an hour or so with constant pressure on the engine to locate slow leaks.
If you are not adding coolant to the radiator, and the coolant level inside the radiator is NOT low, you might have a gauge problem or a problem with the low coolant sensor and not an actual leak in the system.