Heater Problem - Sometimes
I am having a heater problem with my 2001 F-150 4.6 220,000 mile.
After the engine warms up and I turn on the heater, it will blow warm for a couple minutes, then cool off. If I turn the heater off for a while, then back on, it will again blow warm air for a couple minutes. I have read some of the other post on this site and tried the burping recommendation but that did not seem to work.
Thanks in advance,
Ken
Pull off the heater hoses one at a time and make sure you have good flow both into and out of the heater core. If it's not flowing into it you probably have a water pump problem. If it isn't flowing out of it it's plugged.


