poor inside heat

[shelby69]

My brother in law has a 2005 Ford F250 crew cab diesel with an automatic (4X4)

He has two issues:
1) poor interior heat - wife says that the truck will put out warm heat after inital warm up but then goes cold. I did have him verify the coolant level in which he said it was 1/2 gallon low but even after adding the coolant, still no heat. Any suggestion? I have scan gauge for her to view the coolant temperature which may tell us something but any suggestion or help would be appreciated.

2) I have a hard time believing this but the wife says that if she drives the vehicle when cold, the truck will only go 5 mph??????????? What's the story with this - I have a CUMMINs diesel and I can get on the highway even when cold. A friend's 99.5 ford never had this issue, is this something with the 6.0L? He does have a chip, but I do not know the brand.

Thanks ahead of time.

Scott

 

[groundhawg]

There is a shut off valve on the coolant line that feeds the heater core...that could possibly be part of the probelm.

Otherwise, I don't know that the 05s have the same problem with the vaccum in the dash like some of the earlier models did, but it wouldn't hurt to look at the hvac blend door and the vac. lines to be sure that it is all working properly too.

I find the 5mph hard to believe...Mine doesn't run great if you try to push her when it's cold, but that's really no different than any other oilburner I've ever delt with. I'd think that as long as there were no codes and it runs OK after it gets up to operating temp, then maybe it is just a womanly exageration?

 

[shelby69]

Thanks - The speed is definitely when it is cold and not up to temperature - I just have not heard of a situation where a diesel truck will not shift out of 1st just because it is cold outside / engine & tranny are cold.

SAS

 

[shelby69]

coolant shut off valve

Regarding the coolant shut off valve - Does anyone send me a picture of where this is located and if it is electrically or vacuum controlled. Also, if anyone knows if it I can disconnect the connector or plug the vacuum in order to keep it open / take it out of the circuit so I can prove that it is the item that is not allowing the interior to warm up.

I wish I had a haynes manual for his truck but I don't.

Thanks
SAS

 

[shelby69]

Vacuum Leak - reason for no or poor inside heat?

A couple of people had stated maybe the reason why the inside heat is not working is due to a vacuum leak. Does anyone have any good idea of where to start to find the vacuum leak. One member suggested between the hub and the frame? Does he mean that there is a vacuum line on the front hub for 4X4? Any help in finding the vacuum leak would be appreciated.

Scott

 

[snicklas]

shelby69,

I have an 03 6.0 Excursion with my experience the heat should run you out after the engine warms up.

On the cold, no-power issue, do you know if the truck has ever been in and had any of the updates done to the PCM. There is an issue on a cold engine, the oil in the injecters is thick and does not like to flow properly cold startup. There is an inductive injector heating for the PCM that warms the injectors and jelps to eliminate this issue. I had mine done last winter, before I could get no acceleration and was slower to shift, after it would run like a cold diesel as you said your Cummins does. Mine had gotten to the point that sitting in the garage (approx 50-60 degrees) I would plug the block heater in to help with the problem. Being an 05 the engine should still be under warrenty (100K) if the truck is not.

 

[Crumm]

One member suggested between the hub and the frame? Does he mean that there is a vacuum line on the front hub for 4X4? Any help in finding the vacuum leak would be appreciated.

Yes there is a vacuum line down to the hub that runs them. If I remember correctly the line is clipped to the brake line. Look them over real close for signs of damage.

In you other thread you said the engine does not really warm up. I would look into replacing the thermotat.

 

[Zookie400]

somewhat sounds like a thermostat to me also, because sitting idling it will warm up but once you start driving its getting cold again. is that correct?

 

[shhorn68]

My '04 F350 is doing something very similar. The heat will not warm up until you start moving the truck. It also tends to cool back off and then heat up again when switching from defrost to heat and vice versa. I have visited with some of the other guys on the site and I am pretty sure mine is tied to a vacuum problem. I have not located the problem yet but I am going to change out the lines going to the hubs since I think this may be where the issue is.

 

[Zookie400]

I am going to change out the lines going to the hubs since I think this may be where the issue is.

thats a common problem, it would be a safe place to start for sure.