Few days ago truck overheated while driving on the way home. This has never happened before and when I started it up gauge was back to normal. So after doing some research on this great site and pulling some codes using Mike's great tuner it told me of a CHT sensor. So I took it in and it turns out it is under the intake manifold and will cost $600 to replace, they also said Ford put out a TSB on this and recommends replacing cross-pipe and thermostat...$1000 for that job. I dont mind paying but if I had to choose between the two which route should I go and secondly will this "FIX" the problem. The overheat has happened only once. I own a 2007 F350, CC, FX4. Sorry for the long post and thanks for the insight.

 

I thought the CHT only controlled the engine going into limp mode and killing the engine when it got too hot. I thought the coolant temperature sensor was what controlled the temperature gauge, however this could have been on the earlier 2V engines.

The rest of this doesn't really answer your question, but I thought I'd share my experience with this. I've heard that the CHT sensor can be replaced with the intake manifold in place if the alternator is removed, https://www.ford-trucks.com/forums/9...ml#post8614321, but I can see it being possible. As far as the cross-over tube, I can see how that can possibly be replaced with the intake manifold still installed. I recently replaced my crossover since they are prone to pinhole leaks and didn't want to risk it leaking after I already had my intake manifold taken off to replace a leaking gasket. The part was inexpensive, but I also wasn't paying a mechanic to do it since I did the work myself. (As I do with all my vehicles unless they are still under warranty.) The image below only shows the cross over tube and the knock sensor, the CHT is not in this image and would be right above the top edge of the picture.



Hopefully you'll get more information on what the CHT sensor actually does and if it will fix your problem.

 

What was the code? I don't think the issue involved with that TSB threw a code.

 

It was code P1285

 

I just had a similar problem coming home from camping this last Sunday. Doing 60 on flat ground pulling the trailer and get a check gauges warning. The water temp gauge was pegged hot. Shortly after the check engine light came on and it went into limp mode. Truck is an 05 with 50,000 miles, outside temp was about 65. Pulled over and checked the upper radiator hose and valve cover which felt normal. I then cracked the cap on the expansion tank and very little pressure was released. Fluid level was normal. This was only a couple of minutes to check. I then restarted and it ran normal and gauge was back to about mid position. The check engine light remained on. Got home and pulled the code using 5 star Mike's tuner and got a P1299 code. No info was available for the code from the scanner. I assume it's the over temp? This is the first and only time it's happened. Don't mean to high jack the thread, but just thought I'd add my problem to this one. Where is the temp sensor located? I don't see it behind the alternator or any place else. Thanks for any help!

 

WAIT!! WAIT!! WAIT!!
Don't drop a dime for the CHT sensor until you perform the fix as outlined in Ford TSB 06-21-15.
I had the same code and symptoms on my 2006 F350 when I began using it for my hotshot trucking business. Loaded heavy (26K+ total), hard on the throttle to get up to speed, and all of a sudden all the dash lights and buzzers would go off, and the motor goes limp!!
I found the TSB on this forum and ordered the part, installed it the next week and VIOLA, no more false overheat warnings. (I used the truck for 2 years after).
The crossover tube is a bitty to install, requiring all the intake bolts to be loosened enough to lift the intake up about 1 inch. The old tube slips out, the new piece can then be slid into position. Also get the new thermostat as outlined in the TSB. It is different from the original piece, not by much, but enough to make a difference. Don't forget to tighten all the intake bolts and top off the coolant.

 

Thanks for the info PartsPaul. I'll do the TSB first, but I just find it odd that after 50,000 miles a thermostat and crossover tube would just now "act up" and cause an overheat that is reset by turning off and restarting. I am due to change out the coolant so no better time than now to do it! Thanks again.

 

Thanks for the feedback!!

 

Update on my problem....Got another check gauges warning yesterday. Temp gauge pegged again. I was in town doing 40 not towing. I kept rolling down the road and put it in neutral and turned it off and restarted. Gauge went back to normal and did not get the check engine light. I order the crossover and thermostat to do the TSB last week. Should have it Friday and maybe get it installed this weekend. Hope it takes care of the problem.

 

Update on mine, it has not occurred again so I am contemplating doing the TSB. The dealership came in $100 less than my regular mechanic so I dont know what to do. I am taking the truck out of town next week and wondering do I need to do this?? Am I risking damage to the truck not doing it I really would rather not spend the $600??

 

I got the crossover tube, thermostat, gaskets and CHT sensor with shipping from Tousley Ford for $175. I'm going to flush the coolant, change hoses, crossover and thermostat but hold off on the CHT sensor just to see if I get anymore BS overheats. I'm going camping the next 2 weekends after this weekend, so I hope to have the TSB done before the first trip. For sure I'll have it done for the 4th of July trip. I'll let you know what happens.

 

I got the crossover, t-stat and coolant changed this last weekend. Only difference I noticed in the crossover was the hole right below the thermostat was reduced from 1" dia to 3/4". The t-stat was shorter than the original and had holes in the bottom plate where it sets on the 3/4" opening in the crossover. I'll let you know if I have anymore false overheats. I did not change the CHT sensor.

 

So far so good. No false overheats after replacing the crossover and t-stat. Have 2 camping trips done worth about 500 miles and a couple hundred driving around town.

 

Any updates on the fix?. I've got a buddy with a 150 (5.4L) that is having the same false overheat issue. He's done the CHT sensor, harnss and thermostat and it's still doing it so all that is left is the crossover.