Hair pulling problems.
I have a 93 s10 blazer with the w series 4.3L. I ended up having to change my water pump at about 140k km after the it started leaking out the bottom weeping hole. So I replaced the water pump and thermostat, now that was about a month and a half ago. All of a sudden my engine temp has been acting funny, while running at highway speeds and setting my cruise in overdrive it's fine if I down shift to drive the temp builds way up and the check gauge lights come on, put it back to over drive and it's fine, but pulling hills it get warm again. I just changed the thermastat again and still doing it as well as rad cap since I found coolant on the top of my battery and in the insulation under the hood. I don't see any signs of coolant in the oil or oil in the coolant as well as air bubbles coming back to the rad from a blown head gasket. So see I don't know if it's a faulty sensor since I just replaced it a year ago or a bad water pump. But the heater doesn't seem to be putting out an abnormally high heat, but I also notice that when hot the rad cap isn't, the upper hose doesn't seem to have a lot of pressure when squeezed. On a simpler problem I've been having morning sickness with my brakes where before the abs has set itself the brakes will lock up with a very light touch but it only does it in the winter so I'm kind of leaning towards a brake fluid flush. Well I hope you guys out there might be able to help with these problems specially the main one and hope I've given enough info on that one. But thanx for any help and hopefully I can return that help down the road.