I have searched this pretty good on here and I still haven't found an answer. I can't believe (or don't want to) that my problem is a blend door problem.
The output has been lukewarm at best. When I turn the dial from hot to cold I can hear it change and it does change temperature.
I bought a laser temp gun and checked the different hoses. When I pointed it at the hose with the restrictor in it, it read really warm on the engine side of the restrictor but rather cool on the heater core side. At first I didn't know this was a restrictor and thought it was just a clog. After researching this I found out that its to restrict the flow of coolant so the heater core isn't damaged.
This past weekend I had to replace No. 2 coil and sparkplug and to get better access I disconnected this hose from the nipple on the intake (this is a 5.4). I took a light and could see the restrictor. So I took a piece of electrical wire and ran it through the restrictor to see if it was clogged, it wasn't. I blew on the hose with my mouth and water came out of the nipple on the intake that I had taken the hose off from. So this tells me that there isn't a clog.
This is a 2001 with manual heating controls. There is no heat coming out of the rear either.
Does anybody have any idea what this might be? Its going to be getting cold here in Michigan real soon and I don't think my wife will go another winter with the heater working like this.

Thanks in advance, Leinieman

 

Obviously warm the engine up fully before taking any temperature readings.

1. What was the temperature reading on the heater hoses to and from the heater core?
2. Did you check the temperature of the t-stat housing?
3. Have you flushed out the heater cores?

 

I had an issue before last winter with no heat and I was fearng the worst but the het came back to normal after doing a flush, dont know if this crap came from the heater cores themselves or somewhere in the lines but is wasnt nice seeing the crap coming out.

 

Thanks guys I will try the flush. I wasn't going to try it because I have never had luck with it before. But I might as well give it a shot. The only thing its going to cost me is time and some coolant.

Leinieman

 

What did you find? My rear heat isn't working.

 

Sad to say I haven't done it yet. I will try to get to it this week. If this doesn't work I think I will trade the vehicle in.

Leinieman

 

Well, I hope it works then!

 

Well, so far pulled off the rear panel covering the rear heater core. It is a pain. 2 seat belts and tons of trim later, here is the result




Under it, you can see the actuators. The temperature blend is the lower one (the white smaller you see on the side). The panel/floor selector actuator is the top one (you can't actually see it well in this pic, but it is white and sits on top). I pulled the temp one, and I manually held the door open, and it was instant heat, so I know it's just a door problem. I pulled the actuator and just tried to see if moving the switch would move the motor, but it did not. However, I don't know if it is a switch issue or actuator issue. heading to the dealer to get a $60 actuator to see. I have voltage at the plug, but I could never find the pins to show voltage change as if the door was being moved. I will post the results of the new one..

 

 

I've been having no heat issues too. We've replaced so much, the back heat worked until I had a coolant flush done, now I'm lucky to get a blast of luke warm air out of it. Did you figure it out? We've replaced the coolant, t-stat. Blend door and actulator were fine, but the heater hoses do not get warm. SMH..

 

Cold/warm heater lines after the engine is warmed is an indication of a lack of coolent flow through the hoses / heater core/s. Check return flow to the engine.
Hot heater lines and no heat is an air circulation problem.
If you are new to this vehicle you could find a manual coolent valve in the system that a previous owner installed.
I put manual valves in all my vehicles down here in Texas so the heater cores are never hot in the long summers.
Good luck with the project!

 

That's a good idea. How do you open and close it? Where did you buy the valves?

 

Those valves are std. on the older Dodge vans, my '85 D35 had a vacuum operated one over the engine right under the hood. The valve should be available from any parts store.