Have a 97 Ranger, with the 4 cyl. engine,which refuses to give any heat whatsoever. Had the radiator and the heater core flushed out by a local shop and they say the problem is that the heater core needs to be replaced - to the tune of about $900. (Not happening). Both of the hoses are hot and engine temp appears to be normal. In fact, it's almost blowing cool air. Fan works good. I bought a Chilton book(ripoff) and it shows virtually nothing about the duct work, vacuum lines, switches, etc. so I am at a loss as to how to troubleshoot this thing. What's my next move ??

 

Take a look at a Haynes manual. I have never changed the heater core on a Ranger but I cannot imagine it would be much harder than several other vehicles I have changed the cores on. If the core is plugged, you will indeed get no heat. BUT, if the valve that allows the hot water into the core is not opening, you will also have no heat. Check the valve first, if it works, replace the core yourself, probably for about 50 bucks.

 

Unless you see a noticeable leaking of coolant (usually appearing back away from the radiator area, and under the firewall area of your Ranger, along with steaming or light mist of your windsheild) chances are your heater core is plugged, or at least severely restricted.

You say your blower works, and your ducting is intact? Correct thermosat? Blend door normal?...
Have you tried to flush your heater core directly? If not, here's what to do:

Determine the inlet and outlet hoses that go into the firewall area. Cut both hoses about 10" - 12" from the firewall. Through the inlet hose, add some Super Flush. Then, wait at least an hour, 90 minutes. Come back and hook a hose up to the inlet hose. Shoot a stream of water into the core, it will fill up then exit via the outlet hose. You can put a spash deflector so the water coming out will not drain and splash on engine components.

You might be surprised at the amount of muck, junk, rust and setiment comes out of that core, when you may think the cooling system is relatively clean. Also, this is important: If you have access to hot water, running a hard stream of hot water to flush the core will do even a better job of cleaning the core, when it reacts to the flush chemicals inside the core.

Do this for about 10 minutes, and soon you'll see the outlet hose flush out with clean water.

Then simply button up the hoses with nylon plastic connectors and new hose clamps. I like to install a flushing "T" right at that inlet hose that accepts a standard garden hose end. The kind you see available on the Prestone Flushing kits that cost around $3.79 or so.

Some auto parts (NAPA is one) even sell the connectors and flushing "T" seperatly for less than $1 each. Just make sure you use the correct heater hose size connector, and make sure you connect the inlet hose to the inlet hose, and don't cross them, for obvious reasons!!

Just a suggestion. This procedure is easy, cleans a heater core, and simply something to try before having to replace the heater core completely. A clean heater core, with a correctly operating blower, switch, ducting and blend door, you should be baked out of that Ford Ranger with toasty, hot heat! Good luck.

Ed

 

If both hoses are hot that means coolant is circulating through the heater core.
Check the blend doors.
One is stuck shut or broken.
If you remove the glove box interior you can get a better look at the controls.

 

Thanks guys, for the info. Between Murphy's law and a lot of last minute calls, I had to send this "sled" over to another fellow who specializes in automotive AC/heat work. He reported yesterday that the heater core was stopped up and that the blend door was not closing completely. Would imagine I will have another progress report from him sometime tonight, so I'll post same. Thanks again.