How do you change a heater core in a 1989 ford ranger?
First and foremost, always disconnect the battery before working on electrical components. I’m assuming since this is a later model that the heater core is in the cab behind the glove box. Let the engine cool down before doing anything. Once it is cool, drain the coolant into an approved container. Under the hood you need to remove the heater hoses from the core. Get in the cab and take out your glove box. There are 6-8 screws holding the attaching the core to the plenum. Remove them. Unhook the vacuum source, but make sure you leave it attached to the case. It looks like a cable with a little triangle shaped plug on the end of it, I think. Anyway, leave the vacuum harness attached to the cover so it doesn’t become hard to find. Remove the cover and then take the core out of the chamber. When you go to put the new one in, just do what you did to take the old one out backwards. Check it for leaks and be sure to put coolant back in the radiator. If you have an underhood mounted heater co
