Any FORD techs...Excursion Overheat Question

[C-2]

Actually, a code P1299, cylinder head overheat code. I researched it and found it sez a cooling system problem - thermo, temp sensor or head gaskets (no signs of bad gaskets though).
So I was going to replace both - there was plenty of water and oil.
Temp sensor on the computer side, not gauge?
Just out of the blue, for an otherwise trouble-free four years of ownwership.
Any thoughts?

[BDMar]

PM Shadow...

[Kilrtoy]

trade it in and get a new rig

[PHOTOGLOU]

trade it in and get a new rig
If trading it in PLEASE FIX IT FIRST... If your close to Anaheim I would have my guys look at it for you... Jay 714 552 0300

[PHOTOGLOU]

PM Shadow...
Dude your suppost to call me when you get in... Guess your there...

[BDMar]

Dude your suppost to call me when you get in... Guess your there...
Stalker!!:D

[riverroyal]

diesel or V10?My 05 6.0 diesel overheated a bunch,innercooler was cracked

[That Guy]

trade it in and get a new rig
I'm giving you a task for the rest of the week on HB....try and say at least one thing nice....:mad: :D

[502 JET]

Actually, a code P1299, cylinder head overheat code. I researched it and found it sez a cooling system problem - thermo, temp sensor or head gaskets (no signs of bad gaskets though).
So I was going to replace both - there was plenty of water and oil.
Temp sensor on the computer side, not gauge?
Just out of the blue, for an otherwise trouble-free four years of ownership.
Any thoughts?
The cylinder head temp is read by the computer. That's why there was a code set.
There is another sensor/sending unit for the temp gauge.
Did the engine over heat or did the temp go high?
Need to know year and engine size.:confused:

[C-2]

The cylinder head temp is read by the computer. That's why there was a code set.
There is another sensor/sending unit for the temp gauge.
Did the engine over heat or did the temp go high?
Need to know year and engine size.:confused:
Thanks for your willingness to help 502
2003 V10 Excursion 4X4, 64K - all fluids properly filled and this is the only issue i've ever had with the truck.
Wifey sez going down the road, all of a suddeng CE light comes on, check gauges, she sees the water temp rocket to H and the truck lost most of its power. No traffic, going up a small incline, temp was about 100 degrees out - but nothing compared to Havi in 120, with a boat in tow.
After pulling over and restarting, 5 minutes later the temp is back to normal. Nothing remaining except the CE for the P1229 code.
I did some research and sounds like Cylinder Head Sensor (CHT) was tripped, putting the truck into limp mode. I checked the top radiator hose - it was hot, but nonetheless I changed out the thermo. Changed oil and replaced a lot of the coolant. Also noticed I had used regular 5-20W instead of a synthetic blend 5-20W - not sure if that matters.
No water in the oil, and no history of heating up, so I'm hoping it's not a head gasket.
That damn CHT is under the manifold - but I read a shortcut s to remove the alternator to get access. We'll see if it happens again.
Any thoughts?
And man, gotta luv the Internet for vehicle fixes. I also maintain my Mercedes and follow a couple of MB message/tech boards, and have saved a ton from stealership!

[502 JET]

There is no reason to change the CHT sensor, it did its job and is working fine. If it was throwing the light on with no other signs of overheating then you would look into the CHT sensor.
I wouldn't suspect a head gasket unless you are burning coolant, getting coolant in the crankcase, or leaking outside around the heads.
Keep an eye on your engine temp and coolant level. If you are loosing coolant and not burning it or milk shaking the oil look for leaks else where.

[shadow]

Just my opinion for what it's worth,I'm a heavy line Ford Tech been doing it for the past 15yrs.Like 502 stated no reason to change the temp sensor.
Very serioiusly doubt you have a failed head gasket,I've done 100's of cylinder heads on 4.6,5.4 & 6.8's and very rarely have ever had to do one for a blown head gasket.Usually have to do them for valve concerns,piston inspection,oil leaks,blown out spark plugs.
Triton engines will normally not blow a head gasket and if they get hot enough to blow a head gasket they smoke the engine first(99.9%).Seen that over and over.
That being said i would look into your radiator,fan clutch,t stat,coolant level
I've seen Radiators pretty common where it may have 70-90% flow and only be partially clogged which normally won't affect anything but all of a sudden
it is under certain conditions Heat/towing and needs 100% flow and may have 10,20,30% clogged and puts it over the edge and starts to overheat
and without full capacity can't cool back down.Thats just a thought also check your fan clutch and i would recomend a factory Tstat.
Without having the vehicle in front of me it's hard to say.Good luck and if you have any questions shhot me a pm.

[shadow]

By the way i'd run the vehicle up to operating temp and then check both the upper then check the lower radiator hoses for big temp difference by hand if you don't have a temp gun.
If it turns out the radiator is partially clogged flushing it won't do any good,usually by the time debris is clogged in the radiator it's too late and won't flush out.The radiator has plastic tanks and really shouldn't try to be rodded out cause they will never seal the tanks properly again and will fail.

[C-2]

Thanks guys....especially for the encouraging words on the head gaskets, and not having to change out the CHT sensor.
Didn't think about the fan clutch...thought about the raidator but thought still too new - guess not.
The gauges, I read, are set to stay at the middle, or they shoot to oh shiat - nothing in between so it's hard to see if it's warming up?
On the fan clutch - what does it do in the Excursion - spin it faster or is there another fan blade?
I can flush the radiator myself, or is it a dealer dealio?
I replaced the thermo with a factory one, and new gasket.
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Man I hate cooling problems. I once had a GMC 6 pack dually, custom snugtop with polished Alcoa's... with only 26K miles...the truck was 5 years old. We literally only used it to tow to the river.
All of a usdden, it started heating up whenever we put the boat behind it. Replaced fan clutches, added a custom 6 core radiator, added an oil cooler, tranny cooler, completely rebuilt the entire cooling system including head gaskets - nobody (even the dealer) could ever solve the riddle.
Eventually sold it to somebody who didn't have a need to tow. I should have kept that truck!
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Anyhow, will keep an eye on the coolant, I didn't see any obvious leaks. The coolant could have been below the minimum line, not by much, but I was checking everything while parked on a small parking incline.
Thanks again :)

[BoatPI]

If the coolant is full I would place my bet on a stuck thermostat, fan clutch that was not locking up, or radiator hoses that colapse. To answer the clutch question, when the coolant gets hot so does the air passing through the radiator, this causes the thermostat part of the fan clutch to cause the fan to lock up, or not spin freely as it does when closed. When locked up the fan pulls a large volume of air through the fan. In my SD Deisel this usually only comes on when towing, but you can actually hear the fan lock up. I will assume that it uses a thermostst clutch.
Generally one way to see if the clutch is bad, but not a tell all, is to try to spin the fan when the truck is cold. If it spins very freely, then it is usually bad. Also when the truck gets hot, pull over, turn the engine off , grab the fan and try to turn it. It should be very hard to turn as it is in the lock up mode.