2003 Chevy S10, fiancee work truck. Has been leaking radiator fluid. Every time he cranks it, he puts water in it. So, that it doesn’t over heat. I had to drive it the last 2 days. It doesn’t get above 210 it actually 2 notches under that. He’s going to change his plugs and wires today to see if their being steam cleaned but there’s no visible sign of water going away where.
Drive time is maybe 30 minutes to work and from. Minimal traffic or hills.
Standard if this helps.
4 cylinder? 6 cylinder? If one or 2 of the spark plugs are super clean, likely a blown head gasket. In fact, the symptoms just scream “Blown Head Gasket”
look for coolant residue with a flashlight and mirror
It’ll be obvious if the radiator, water pump, etc. are leaking
If you have the 4.3 liter V6, you’re going to have to look extremely hard at the lower intake manifold, the front timing cover and the bellhousing area. If you see ANY coolant residue between the intake manifold and the valve cover gaskets, the lower intake gaskets are goners. If you see any coolant trickling down the front or back of the engine, again, the lower intake gaskets are goners.
So you said leaking radiator fluid though you cannot see drips on the ground? As mentioned I’d look all over the engine bay compartment, top and underneath, for fluid after it has been running.
If it is an internal coolant headgasket leak, which means coolant is getting into the oil, I’d recommend “Bar’s Leaks Blown Head Gasket Repair (HG-1)” which is like $40 and there’s a $10 rebate. You just pour it into the radiator and don’t have to drain anything. If you do that and the coolant loss stops, then you know the headgasket(s) are the issue and should look into that.
If it is a leaking radiator you should be able to see coolant leaking on the ground from the front. If it’s leaking externally, such as from the radiator or a coolant hose then you should be able to find coolant on the ground or somewhere in the engine bay after it’s running, or steam from it burning off.