I have a '97 Chevy S-10 2.2 with 208K miles. Today on the way to work the heat cut out suddenly.I have had an issue with my engine where the temp will go up and down while on the highway but maxes out at like 215. Today after the heat cut out it was getting up near the redline before going back down to 150.I made sure the coolant was good before coming home but on the way home it was doing the same thing. I changed the thermostat but it's still doing the same thing.When I rev the engine I can see the upper radiator hose collapsing so it seems like there's a clog somewhere but I don't know how to find it. I guess it could be the water pump but then what is causing the suction on the upper radiator hose?Anyone have any ideas?
doesnt sound like water pump you may have lost a heater core thats what it sounds like to me its getting vacuum and temp is jumping but you dont have heat sounds like it to me check that next but as with the other selection check if your thermostat is in wrong
if the top radiator is collapsing then the radiator is clogged up ! i doubt it,s the water pump ! try this ! once the engine is hot, shut it down and feel the radiator fins next to the fan ! if you feel cold spots then the radiator is clogged in some places ! flush out the whole cooling system ! i had a ford truck that did the same thing until i bought a new radiator !
You have a leak in a hose. I would suspect a heater hose or lower radiator hose. When you put water into the radiator, you still had air in the system, this prevents you from having the required amount of coolant in the system. Find the leak, fix the leak. Jack up the front of the truck to where the radiator cap is at the highest point in the system, then add coolant. Problem solved.
The possibility that the thermostat is up side down comes to mind. Chevy water pumps have been known to loose an impeller, but the collapsing upper hose suggests a vacuum is being pulled, so I don't think it is the water pump.
