heater problems

With the engine at full operating temp, locate the 2 heater hoses where they go into the firewall and feel them to see if they are both hot to the touch. If not too hot to hold, then you have to look at the actual engine temp and if that is up, if it is, then your looking at a restricted heater core.
If you find that they are both too hot to hold, then the heat in that vehicle is controlled by a blend door that regulates heated air flow. it is operated by an electric motor/actuator. The problem can be that the actuator is stripped or inoperative or the door itself could be damaged. This is what needs to be determined by examining the actuator and see if it is responding to heat change commands or not.

Check out this guide

https://www.2carpros.com/articles/car-heater-not-working

If they are both not too hot to hold on to, then you either have a restricted heater core or the system is not completely full and getting air pockets for some reason.

Replaced stuck open thermostat-did not help. Re: heater core hoses-one is hotter than the other but not too hot to touch at full operating temp.

Cannot find heater control valve in heater hose that should be there per car books and internet? Is this missing? (Just bought this car.)

Are there self-test diagnostics on Climate Control Panel? Using manual override not EATC.

Going to remove heater hoses and try to flush core while still in car as not looking forward to removing entire dash to replace heater core. Would full radiator system flush heater core as well?

How do you clear air pockets from system?

Thank you very much for your assistance. I appreciate knowledgable help such as yours.

From what you're describing, the core is plugged up. You can try removing the hoses and back flushing it with water pressure but you will probably need a new heater core.

I think you are correct. I will try flushing just the core but would a full cooling system flush be advised as well in addition to this or maybe instead of this?

What about the missing heater control valve?

It might be a good idea to clean the rest of the system if it shows any sign of contamination but your problem right now is with the heater core so that needs special attention.

I appreciate your replies. I am flushing the heater core right now.

Do you know anything about the missing "heater control valve"? It is supposed to be inline in one of the the heater core hoses but it is not there.

Apparently you didn't read my first post. This car uses an air blend door, not a water valve. Coolant circulates 100% of the time

I did read your post but misunderstood. Sorry. I thought it had both components. I have researched this so much I have confused myself beyond the point of return as both parts are listed everywhere for this model and in the repair manuals as well. I flushed the heater core and now both hoses get hot evenly but still no heat. I am now researching replacing the air blend door which looks worse than replacing the heater core.

I think I'll take a break as it is near 70 degrees and will be near 80 degrees tomorrow. But I'll need heat next week.

I really appreciate your assistance with this. Thank you for your time.

The door itself is about 8 hours to change but the actuator is the more common failure. You will have to remove the actuator to see if the door is stuck or damaged.

Got it. Thanks. Looks like I might as well replace the heater core while all this is undone anyway.

Only if your going after the door itself. It requires removing the entire dash, the entire HVAC and disassembling it.

Well, there is no A/C either. So it's the actuator? How do I differentiate between the actuator and the door? Can you tell if the door works manually once I get in there? I understand Lincoln had a problem with the actuator in this series.
Does this look accurate?
http://www.markviii.org/LOD2/blend_door_repair.htm
Thank you so much.

Oh, that link was the wrong make and model. My gear shifter is on the column. Sorry. Out here by myself tryig to figure this thing out and just overwhelmed at the moment.

You have a Town Car. That is a Mark VIII.

The instructions still say the dash has to be removed to access it but you may be able to at least see it by removing the glove box. It is mounted on top of the HVAC housing.

Yeah, I screwed up.
Now i am looking at this as I can't find anything closer:
http://wiki.answers.com/Q/How_do_you_access_your_blend_door_actuator_motor_in_your_1993_Lincoln_town_car#ixzz1Mxn3CaV9
Thanks for the drawing. Apparently I am needing all the help I can get with this thing.

I don't suggest you attempt this but if you do, go purchase some service manuals first.

Well, it's me or no heat and air. Surfing for service manuals as we speak.

Hey, can you do this? What happens when you need defrost and heat at the same time then?

"I had a 1995 TC that the blend door actuator went out on and I simply unplugged the power to the actuator and moved the door manually with a screwdriver from right to left depending on if I wanted heat in the winter or A/C in the summer. Not the best fix but I only had to get under the dash twice a year.'
I'm getting desperate here! LOL!

If you can access it and the door itself isn't broken, that is possible. I have a Jeep i do that to because I haven't got around to fixing it but that one is much more accessible than yours.

Well you can bet I'm going to give it a try because between paying for the car and getting it to pass emissions (hell) I'm running low in funds and patience.
I just can't thank you enough for all your help.

Just make sure both of those hoses are hot before you blame the blend door.

Well, they are both equally hot now that the heater core was flushed and the hoses and with the discovery of no cold from the A/C I'm pretty sure but it's still a crap shoot. Unless the heater core is still stuck and the compressor is not working or out of refrigerant too. This car did sit for a long time before I bought her so always these things can show up one at a time.

Finally getting back to this....Thermostat replaced, heater core flushed. Blend door actuator not working but if I rig it so the blend door is wide open I get full A/C. It is my understanding that I should be able to rig it closed and get full heat but only cool air comes out even on manual override. There is no heater control valve in this year and model in the heater core intake hose. What am I still missing?

Thank you so much.

With the engine at full operating temp, locate the 2 heater hoses where they go into the firewall and feel them to see if they are both hot to the touch. If not too hot to hold, then you have to look at the actual engine temp and if that is up, if it is, then your looking at a restricted heater core.

Both heater hoses are fully and equally hot. Moving the blend door manually and having the heat on manual override does not help. What next? Thanks.

You're blend door CANNOT be working properly if that is true.

The blend door does not work but I can move it manually and get full A/C when it is wide open on manual override so I should be able to move it the other way and get full heat on manual override but that is not happening. Is there a blockage somewhere else? Vacuum line behind the glove box? Or?

That was supposed to say "without removing the dash".

OK, well it did not post at all so here goes again....

Inconsistient a/c and heat problem. Initially little of either on EAC.

Had full heat this AM on mannual override. Then not this afternoon. Had full A/C on manual override but lost it too. I assume I bound by 60 to 90 degree range even on manual override but it is not consistient.

No air coming from defroster either even when heat was on floor.

Found blend door and actuator. Would like to replace or switch to heat only for winter then a/c for summer but not sure how to do this without removing the dash.

Is there a vacuum problem and if so where?

I've already told you what the problem is. There is no vacuum associated.

I ran the EATC on-board diagnostics and now the blend door moves and responds to the thermostatic controls. (?) The outside temp is reading much higher than actual. It's still too close to the max temp range (90) to tell if the heat is getting hot or just warm like last winter.

Where are the vacuum lines I should check located? I've been told there are some under the dash which I can't get to without pulling it and some somewhere on the firewall in the engine compartment.

Where is the outside temperature sensor located?

Where is the evaporator case drain located?

What else?

Have full A/C but no heat again this AM. Within norm op range for EATC and engine. Humid in car while running yet it is very dry here. Self diag error code 025. Reset and ran several times and ran again to verify.

Blend door actuator replaced. Vacuum lines checked. All works normally now but still no defrost. Now what am I missing?

CORRECTION: Blend door actuator replaced. Vacuum lines checked. All works normally now but still no defrost and heat comes out of a/c vents. Now what am I missing?

****UPDATE:****The dash is out again so I checked vacuum lines manually and the floor/defrost door, panel door (heater air damper door), and the recirculating air door all respond.
I have diagnostics and instructions for a Heater Control Cable replacement but there is not one attached to the EATC module nor is there a place that one would go so how does the EATC decide "defrost only" on mannual override when there is no dedicated defrost vacuum line or cable?
Also, is heat supposed to come out of the panel vents or just the floor and the defrost vents? When it is on "floor" on manual override the heat comes out of the panel vents also even when you select 60 degrees on the temperature selector.
Thanks so much for replying. It's starting to get cold here (Colorado) and I'm in panic mode as I'm traveling a lot between here and Wyoming and need her fixed so I can work. One more day off - need to find it soon!
Traci

Now I am looking for the interior temperature sensor location as there is some erratic behavior. When the heater gets hot then it suddenly gets lower and when the a/c gets cold then it suddenly gets warmer. It's like the interior air temperature sensor is in the airflow somewhere and is "correcting" the temperature it's calling for.

Still no air out of defrost ever.

What a nightmare.

**UPDATE 09/13/2011**
After blend door actuator replacement the A/C appears to work normally. The heating system still has the following problems:

THE TWO PRIMARY PROBLEMS ARE LOW HEAT QUALITY AND DEFROST BLOWS ONLY COLD AIR. ALSO LOW VOLUME BLOWER.

On any setting the heat at max (90 deg) does not heat the interior to more than approx upper 60s. A/C temp setting to actual appears correct but heat temp setting to actual is about 10-15 degrees off. Air is just lukewarm when asking for heat.

Even at 90 deg setting when switching to defrost it blows cold air only out the windshield vents.

All air all the time blows out of panel vents and must be manually redirected to floor or defrost by shutting the panel vents. But this may be just how the system operates (?)

Blower appears very low at all settings particularly defrost. It does go higher at manual (turn wheel) but seems low to me.

When switching to vent from any heat setting the air appears to be slightly warmer.

Covering the solar sensor changes nothing regarding defrost but I still don’t know if the solar sensor even has anything to do with the EATC.

What am I missing now?

Heater problem
1995 Lincoln Town Car V8 Four Wheel Drive Automatic

hi sir,

i have town car 1995 , the problem is when i used the heater still the air coming cold

Check if engine warming up and if not remove and replace thermostat
check coolant level and if low add as needed
if all OK suspect blend door motor in the HVAC box
try and get the codes