Where is the cylinder head sensor located? Just because the code is kicked out may not mean the cylinder head temp is out of range. Tuners will read (at least some will) the output from the sensors in real time. Has this been done or can it be done for this sensor? Hard to believe that it hasnt been done. But then, this problem hasnt been solved either. He says the temp goes down then up and "---all of a sudden goes all the way up to hot and the check engine light comes on" Sounds like a flakey sensor to me or even a bad connection at the sensor.

 

Just a guess! In one of his earliest posts he referred to having used Barrs Leak and flushing out a wad of the stuff from the heater core, so I'm guessing that theres another wad of it in a cooling passage of the heads or block and it only gets ino a place to cause problems when the engine is fully warmed up and/or at highway speeds. I think he will have to use an infra red temp gauge with a laser pointer to check for hot spots on the engine block and heads. "Harbor Freight" sells them for less than $20.00 at times. I would run the truck in the drive way at about 2500 rpm until it starts to cook and then start looking for hot spots. If you won't do this the dealer will for about $85.00 per hour.

 

Yep MM, I will drink to that one!! Maybe it a piece of "floating" debris from the stop leak that moves to block a passage when the water pump stirs it up a little.

 

Why was Barrs Leak in the system in the first place? Leaky heater core, radiator, suspected bad head gasket? If it clogged the system that bad it sounds like more than one can was used.

 

Still thinking it's your head gasket. Everything sounds real similar from another post I worked where it ended up being the head gasket. Read this. https://www.ford-trucks.com/forums/7...-problems.html

 

just dropped it back off at the radiator shop he is going to check the head gaskets in the am just to rule them out.

 

Be sure to let us know what you find out.

 

zed - I've been lurking and watching your thread with great interest. I'm fighting similar symptoms with my '98 Expedition (205k miles and running strong). Somehow air gets into the system when the heat is on... what is different is that I am having no problems at all with heat off (and system burped) or when running the AC.

Have you tried either of these options?

 

well the rad shop said the water pump is mint thermo is great and one of the head gaskets is cracked just enough to let it pressure up the system keeping the coolant off the thermo and causeing my problem. any body know a quick fix?????

 

Yep, sure do--. Pull the head and replace the gasket While U R at it, prob should replace both----or----run it til it quits and it wont be worth much of anything.

 

WHO's YOUR DADDY, Sorry, I just love it when I'm right. Like I mentioned in my first post you might look into trying this stuff Repairs Blown Head Gaskets With No Disassembly | Lifetime Guarantee | Steel Seal I haven't heard of anyone who's tried any of this yet however at this point what have you got to loose

 

I watched their video and it reminds me of all the snake oils I have ever seen, including the vitamin "infomercials" on TV. Dont get me wrong, would be nice if it worked, maybe it will-----for a while. Maybe you could give it a try, but I would not look for it to work long and then when you do have to pull the head, I'll bet its a mess----if you can break it loose.

Since there is no evidence that its leaking out to the ground, then it has to be going into the block (pan) or a cylinder. If it reacts to high heat (per the video) what happens when it hits the cylinder--valve seats--rings & grooves and solidifies? If its the pan, then what happens to the filter, change it fairly quickly?

I dont know the book values on early expys, so if you try it, might want to save up for a repair/long block/ or sell.

I do hope it works for what you want

 

If I myself were looking at $1000 + for head gasket repairs or $80 for a product that might save me having to spend the $1000 +, guess which route I'd go. They advertise a lifetime gaurantee so if it doesn't work, get your money back. There again at this point what do you have to loose.

 

I agree with all that . But that dosnt alter the fact that no one in including you and I that we know has tried it. Dont know if I am an older fart than you , but I have yet to see any of these that are really a good cure---temporary at best. I spent a bit of money on STP way back----never proved a damn thing

These are all just opinions (yea, I know the other part of that statement ). As long as he makes an involved decision is good. After all, its his expy---and LOL.

 

well i just got it back from the radiator shop and he did the hydrocarbon test and found OVER 500ppm pointing towards the gasket.anybody know a good rebuilt for sale???lol or some good beer?