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2.5L ('98-'01) Heater control valve vacuum line


Kiyp

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So while trying to diagnose why i have no heat in my truck i found that the heater control valve was missing the vacuum line and i cant find any disconnected lines anywhere, i also cant find any mention of where the other end of the line is, i tried pressing the valve manually and when pressed in it leaked fluid so it does need to be replaced however that does me no good if i cant find the vacuum line that controls it, its getting cold out down here in Florida and i drive for a living so i could really use some help on getting this fixed, its a 2.5l 1999 ranger. Ive heard the vacuum lines are a bit different on the 99 but i cant find any information on how it is
 


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DILLARD000

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That missing\disconnected vacuum line has to be laying somewhere loose on the right side of the engine compartment?
Do you have the HeaterControlValve with 4HoseBarbs or the simpler one with 2HoseBarbs?
If you got the simpler one, recommend getting rid of that junk plastic factory BallValve,
& replace it with a VacuumToClose AllMetal PlugValve, like the 4SeasonsFactoryAir# 74603.


 

Kiyp

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That missing\disconnected vacuum line has to be laying somewhere loose on the right side of the engine compartment?
Do you have the HeaterControlValve with 4HoseBarbs or the simpler one with 2HoseBarbs?
If you got the simpler one, recommend getting rid of that junk plastic factory BallValve,
& replace it with a VacuumToClose AllMetal PlugValve, like the 4SeasonsFactoryAir# 74603.


Its a 4 valve
 

Kiyp

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I spent hours today looking and just cannot find an unused vacuum line asside from one on the drivers side with a bolt in it, but that was like that when i bought the truck and im fairly certain i had heat in here a year ago, could be mistaken as i do have bad issues with my memory but im pretty sure
 

DILLARD000

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That vacuum line should come from the back of the AC controls in the dash.
 

Kiyp

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That vacuum line should come from the back of the AC controls in the dash.
I see that particular line but it connects with a completely different line, it comes out of the dash, then connects to a white line that coes under the resivoures, then at some point appears to connect with a black vacuum line that snakes back out from under the resivours which connects to a red line that travels to the driver's side and connects to the break booster line
 

DILLARD000

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HeaterControlValve vacuum line may be the same small vac hose with a Tee that controls the AC damper\vane in the dash.
 

Kiyp

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HeaterControlValve vacuum line may be the same small vac hose with a Tee that controls the AC damper\vane in the dash.
That may be the case, issue is there is only a right angle connector. No T fitting
 

DILLARD000

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If you had good heat control last winter, but not now, something has broke or been changed.
Keep looking.
 

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In a 1999 Ranger the 4 hose by-pass valve in the engine bay is only used in MAX AC setting, it SHUTS OFF flow thru heater core in the cab when Vacuum is applied, so no vacuum = HEAT in the cab
Vacuum hose for this comes out of the firewall and will be GREY in color, looks like a "wire" because its a hard plastic vacuum line

For a test, after engine is warmed up, feel BOTH heater hoses at the firewall, it both are hot then "valve" is fine, you have flow thru heater core
If only one is hot then you have a blocked heater core, wait until engine cools off and pull hoses off heater core and use a garden hose to back flush and flush the core

No heat in a 1995 and up Ranger usually means the Blend Door actuator in the cab is broken, this is an electric motor
It is controlled by the TEMP knob on the dash
Blend door routes air from the fan thru the heater core(HOT) or around the heater core(COLD) or any where in between

Google: Ranger blend door

Loads of videos and how-tos to test this or repair this
 

Kiyp

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In a 1999 Ranger the 4 hose by-pass valve in the engine bay is only used in MAX AC setting, it SHUTS OFF flow thru heater core in the cab when Vacuum is applied, so no vacuum = HEAT in the cab
Vacuum hose for this comes out of the firewall and will be GREY in color, looks like a "wire" because its a hard plastic vacuum line

For a test, after engine is warmed up, feel BOTH heater hoses at the firewall, it both are hot then "valve" is fine, you have flow thru heater core
If only one is hot then you have a blocked heater core, wait until engine cools off and pull hoses off heater core and use a garden hose to back flush and flush the core

No heat in a 1995 and up Ranger usually means the Blend Door actuator in the cab is broken, this is an electric motor
It is controlled by the TEMP knob on the dash
Blend door routes air from the fan thru the heater core(HOT) or around the heater core(COLD) or any where in between

Google: Ranger blend door

Loads of videos and how-tos to test this or repair this
Blend door actuator is fine, cut hole in the botto. To test and if broken replace the blend door however no matter the position there is no heat, both hoses were hot however one is hotter than the other, however the valve does appear to be open, a bit leaky though, this indicates there is flow through the heater core even if it is slow so i am unsure why i would not get any heat through it, my blower motor does work properly as well
 

Kiyp

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If you had good heat control last winter, but not now, something has broke or been changed.
Keep looking.
Issue is im not 100% sure i did have it as i have memory issues and this is my second truck, first one had catastrophic engine failure not long after i got it
 

RonD

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Heater core can be blocked and still have flow thru the top part

I would try flushing the core with garden hose, see what kind of flow you have thru the core

You can remove the heater hoses at the bypass valve and point one down at the ground and put garden hose on other one
Then REVERSE and back flush the other way

If core seems blocked you can mix CLR or Vinegar with some hot water and pour it into the core, let it sit for 20min and flush
Repeat as you see fit

Just a heads up, you should reverse the heater hoses at the firewall, on ANY vehicle, every 2 years or when you change coolant
Heater cores have no "direction" of flow, by reversing the flow you will keep it cleaner so it lasts longer
 
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Kiyp

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Heater core can be blocked and still have flow thru the top part

I would try flushing the core with garden hose, see what kind of flow you have thru the core

You can remove the heater hoses at the bypass valve and point one down at the ground and put garden hose on other one
Then REVERSE and back flush the otherway

Just a heads up, you should reverse the heater hoses at the firewall every 2 years when you change coolant
Heater cores have no "direction" of flow, by reversing the flow you will keep it cleaner so it last longer
Good tip, will probably try that tomorrow or something i am just about to start working for the night so i sadly just have to deal with the cold. I would love to hear any other tips or input anyone else here has to say
 


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