I have a question guys. Yesterday my girlfriend, her brother and I were all going down the highway in my truck, and the heater just started pouring out cold air. I can't get it to blow hot air at all. Is it the heater core or something? The checkengine light came on also when this happend and is still on.

 

Have you checked the heater hoses going to the core? One should be hot and and the other warm. Either something has blocked the heater core or some other item has an issue. Since the check engine light is on, it might have something to do with the flow of coolant in the engine or the lack of causing hot spots. Have you checked for bubbles in the coolant?

 

radiator full?

 

Ya the radiator is full lol. I turned it on just to see what would happen and it started blowing hot air again. Sometimes it will blow cold air for like 10sec then go back to hot. I was doing some airintake work on my truck and saw that the hose that runs from the valve cover, to the air intake had come almost off. Could this have had anything to do with it? I pushed it back on. It had come loose from the airbox end.

 

Yup, a air vacuum leak would cause this, check all vacuum lines.

 

I've had to add water to the radiator every so often. Today I was under the truck and saw that what looks like the water pump is leaking a little. It could also just be the hose loose although it didn't feel loose.

 

Usually when a water pump goes out, it will leak out of the hole from the bottom of the water pump. Use a bright flash light to spot out those leaks, check all the lower radiator hoses, and around the water pump gasket, and the hole at the bottom of water pump.

 

I'll have to do that because there IS water coming from somewhere right there. I bet that is what it is. Before I bought this pickup I had a Cadillac Seville and that thing went through water pumps like crazy. It would do the same thing this engine is doing. I ran that engine ALOT harder though lol.

 

I do not know if you fixed the problem, but I had a similar problem with my 97 4.2L F150, it was not putting out heat, only cold, added antifreeze a few times as it was low, turned out to be the damn intake gaskets leaking and i was loosing coolant and not getting enough antifreeze into the heater core to make hot air.

replaced the lower intake gaskets and the problem is fixed, also had the dreaded hydrolock antifreeze in cylinders and blowing out exhaust, also had to replace the O2 sensors.

Moral of story, if you are losing antifreeze and not getting heat from heater, watch out for hydrolock!!

 

Dan, I know this is not your fault, per se, but for a '97 F150 to have problems like that, is terrible in my opinion. Bad design, parts material, etc. but things like this should not happen. I mean, when we're doing maintenence on our Fords, how many times do any of us think: "Okay, time to check and see if intake gaskets are leaking". Ed (shaking head in disbelief) Ford, must correct stuff like this...

 

Ed,

Yes you are right, I obviously did not know of the faulty gasket design untill after i bought the truck. I bet the guy who traded it in know of this problem. I bought the truck from a dealership I have had it since Dec 94 it had about 89K miles on it. I was lucky enough to find out about the hydrolock (on this website) problem about 3 weeks prior to it happening to my truck. At 103K (about 2 months back)I had white smoke in the exhaust at start up, then started to notice the antifreeze level dropping in the overflow bottle. I added antifreeze thinking this hydrolock thing can't be happening to me. after i added antifreeze the third time i was convinced i had fallen prey to fords design flaws. came out of work one day to go to lunch and you guessed it, no start just a click click click. Tried to jump start it, thank god it would not start. Remembering the hyrolock problem i decided it was time to remove some plugs and see what i find.......I found antifreeze in 2 cylinders on drivers side. drained the cylinders, dried out the plugs and drove it straight to a shop. $600.00 later it was all fixed, well so i thought, the Check Engine light came on 3 days later and I had to replace a 02 sensor that died trying to measure H2O not O2.

I can not believe that ford knows this problem exists and refuses to honor any type of warrenty or compensation. I love the truck and I hope it will last many more years since i took care of the catastrophic engineering flaw. Ford Quality is not in the Job! Oh yeah when i called the ford dealer (who knows this prob exists), they acted like they have never seen this before and they told me I would probably need a rebuilt engine and maybe had a cracked head or block, thans ford for making a P.O.S. gasket and then trying top sell me a new engine. I wonder how many people have fallen prey to this scam?

Now for my AC problem........................that is in another post.

Dan

 

I have a 2000 F150 5.4L with the same problem. After attempting some quick fixes, that did not work, I also took it to ford and after 4 days of not fixing the problem, they told me that I need to replace my passenger head for a mere $1,800.00. I choked on their words, and have found some excellent advice on this web site. Replaced my intake manifold gaskets, and now the rough idle has disappeared, but now having the loss of heat and rise in engine temp. Once I fix one thing, something else pops up. Still working on this problem and not convinced of a cracked head. But, the more I read, the more I realize why I swore I would never buy a Ford again - when they refused to help me out on my last one, 98 Explorer, when the air bag light came on less than 100 mi over warranty. It was clear to me then that they did not care about their vehicle owners. I can only swear to you today that I will never buy another Ford again. I am looking at the Tundra for my next purchase!

Fed up with Ford!