I am a bona-fied hero .. .. at least with my wife I am.

She has been complaining about how cold it is in her '99 Taurus wagon, lousy heater and all ... "I need a new car.", etc.. I did a little inet research and discovered that indeed the heater core inlet (on the firewall more or less in front of the driver) and bypass hoses were both significantly warmer than the outlet hose coming out of the firewall in front of the passenger position. This I was told indicated a clogged heater core and to cure the problem I should backflush it.

Two 4' lengths (for convenience) of 5/8" heater hose and a short chunk or a plug for the inlet T to keep the antifreeze in the engine, a 5/8" female garden hose barb, a 5/8" hose barb connector, a few #10 clamps and one of those garden hose sprayers with handle and the hose threads on the nozzle and I was ready to go.

The backflush is pretty simple but I learned a couple things to get a good flush. Not much moved until I started using hot water and used the hose nozzle to put sharp on-off pulses against the crud in the core. I had the discharge hose jumping!! That combination really moved out the junk!! I had a white 5 gal bucket that I directed the flush water into so I could see how clean it was coming out and I filled it five or six times before the water started to clear.

We took her car to run some errands that afternoon and it was really fun to watch her as she loosened up her coat and finally reached over to turn down the temp control ****. She said that was the first time she had ever turned down the heat in that car since we've owned it. She LOVED IT!!

It worked so well I'm thinking of doing it to my car just to see if it makes any difference.

Roger

(now for the disclaimers ... hot coolant can scald you, don't apply high pressure directly to a low pressure heater core, wear eyes protection, etc.)

 

A word of warning. Some heater cores are not very rugged and may not stand up to the pressures you can get from a garden hose. If you are unlucky, the core can spring a leak if the pressure gets too high. Replacing the core in late 80s early 90s Tauruses is an expensive proposition, $600 and up, I assume the later models are similar, so you don't want to pop that core.

In your case, you pretty much didn't have anything to loose anyway so blasting the core worked for you.

Some heating circuits have a restrictor valve in the hose. Usually a plastic housing in the hose before the inlet in the firewall. This is often the part that is clogged and just flushing that part may get things moving for you.

After unclogging a heater core, I like to do a thorough chemical flush of the system.

Good Luck,

Jim Henderson