A/C does not blow cold air

[h0op521]

2002 Ford Explorer XLT

My A/C is not blowing cold air. The A/C clutch engages albeit for a short cycle. The low pressure looks normal, but the high pressure does not.

Can someone help me diagnose this? Is the high pressure line clogged? Does this mean I need to replace the orifice tube?

Here's a video of the A/C Manifold reading

Thanks in advance.

 

[shucker1]

Low on charge but the flutter on the high pressure gauge when the clutch cycles looks strange.

I like to see my high side in the 225 range.

 

[h0op521]

Low on charge but the flutter on the high pressure gauge when the clutch cycles looks strange.

I like to see my high side in the 225 range.

I recharged the system, so I don’t think that’s the problem.

I don’t have any experience working on car A/C, but I think the high pressure line is clogged somewhere. Maybe, the orifice tube is clogged so the high pressure is not converting to low pressure in order to get cold

the high pressure reading on the manifold gauge looks very strange. I’m hoping someone can help me further diagnose based on the manifold gauge reading.

It’s also worth noting that the A/C compressor clutch cycles off very quickly. I’m not convinced that the compressor is bad because it does cycle on, but what causes it to cycle off so quickly?

 

[Josef161]

A very common problem is that the blenddoor breaks. There is a trick on how to"fix"it. Buy a package of wooden meat sticks (should be about 3mm in diameter) and then stick one of them in the vent. You need to stick it in the vent that is in the center on the leftern side (on the rightern top of this vent). That should fix your problem.

 

[shucker1]

I don’t have any experience working on car A/C, but I think the high pressure line is clogged somewhere. Maybe, the orifice tube is clogged so the high pressure is not converting to low pressure in order to get cold

If you had a correct charge and your high side line was clogged as you mentioned then your high side pressure would be off the scale.

I still think your low on charge.

How much Freon did you put in?

 

[shucker1]

It’s also worth noting that the A/C compressor clutch cycles off very quickly. I’m not convinced that the compressor is bad because it does cycle on, but what causes it to cycle off so quickly?

As your low side pressure drops with the compressor running it trips the low pressure safety switch located on the side of the accumulator.

Usually about 20 PSI.

Compressor stops and pressure starts to go up resetting the switch and the compressor comes back on.

 

[h0op521]

If you had a correct charge and your high side line was clogged as you mentioned then your high side pressure would be off the scale.

I still think your low on charge.

How much Freon did you put in?

Ok, so I have an update. I had a local shop evacuate the system, then I went to AutoZone and replaced the orifice tube and brought the car back to the shop to fully recharge the system. The old orifice tube had a little but of debris, but it wasn't too bad, so I was pretty sure that would not fix the problem.

The system takes 3.5 lb refrigerant, so I did not previously have it fully charged. But even filling the refrigerant all the way at the shop did not solve the problem. The A/C still blows hot air. The high pressure gauge still flutters like it did in the video I previously posted, albeit at a high pressure this time.

The shop owner thinks I have a clog or possibly a "collapsed hose" somewhere in the system. He evacuated the system again, and he suggested that I try to flush out the high pressure line and then bring it back to the shop to try again. Thankfully he did not charge me for any of this.

I'm not 100% sure how I'm going to flush out the high pressure line yet. I need to do some more research.

I was in a rush to get out of the shop, and I wish I would have spent more time asking questions and diagnosing the issue further. He mentioned some of the lines under the hood were running cold, but we didn't follow the line throughout the hood to see where the pressure dropped.

Now I'm thinking that the problem could possibly be the condenser or the receiver dryer / accumulator.

Any advice is greatly appreciated.

 

[h0op521]

As your low side pressure drops with the compressor running it trips the low pressure safety switch located on the side of the accumulator.

Usually about 20 PSI.

Compressor stops and pressure starts to go up resetting the switch and the compressor comes back on.

Got it, that makes sense. So, I think this confirms that the pressure safety switch is working properly.

 

[h0op521]

A very common problem is that the blenddoor breaks. There is a trick on how to"fix"it. Buy a package of wooden meat sticks (should be about 3mm in diameter) and then stick one of them in the vent. You need to stick it in the vent that is in the center on the leftern side (on the rightern top of this vent). That should fix your problem.

Hi Josef. Thanks for your reply. Can you clarify a few things, please... Which blend door are you referring to? Also, where exactly is the blend door located? Do I access the blend door from the cabin (behind the passenger side dash) or from under the hood near the firewall?

Since we're on the topic, there's actually a separate issue that I'm also working on. The air flow in the vents in the front row of the cabin blow very weak. After doing some research, I believe there's a door that is probably broken behind the passenger dash that is preventing the strong air flow.

The rear vents (controlled separately, I believe) has normal airflow, but the air is hot, even when the A/C is on.

I believe these are two separate issues - 1) weak air flow through front vents, and 2) hot air blowing throughout the cabin when the A/C is on

Lastly, about a month ago I replaced the heater blend door actuator because when I would change the temperature I would get the clicking noise. Replacing the heater blend door actuator fixed the clicking noise, and as I mentioned, now the A/C clutch turns on when I switch to A/C

 

[shucker1]

The system takes 3.5 lb refrigerant, so I did not previously have it fully charged. But even filling the refrigerant all the way at the shop did not solve the problem. The A/C still blows hot air. The high pressure gauge still flutters like it did in the video I previously posted, albeit at a high pressure this time.

What were the high and low numbers?

 

[h0op521]

What were the high and low numbers?

Unfortunately, I did not get a good view of the high and low numbers after he fully charged it. All I could see is that the high pressure needle was fluttering the same way that it was in the video I previously posted.

*** Edit *** If memory serves, I think the high pressure needle was fluttering somewhere around 350 PSI, but I can't say that with a lot of confidence.

 

[shucker1]

350 is excessively high IMO.

I shoot for 225 High and 35-40 low side in south Louisiana.

I do it with windows open and blower on high, re circulation off.

I'm actually trying to "Boil" the refrigerant as it appears in a low pressure liquid state in the evaporator.

Thus drawing in heat and changing phase of the freon to a low pressure gas...

 

[DanHerndon]

2002 Ford Explorer XLT

My A/C is not blowing cold air. The A/C clutch engages albeit for a short cycle. The low pressure looks normal, but the high pressure does not.

Can someone help me diagnose this? Is the high pressure line clogged? Does this mean I need to replace the orifice tube?

Here's a video of the A/C Manifold reading

Thanks in advance.

Understanding Normal AC Pressure Gauge Readings

Learn why normal AC pressure gauge readings are essential for diagnosing car AC problems. Don't rely on just the low-pressure gauge

ricksfreeautorepairadvice.com

This might help

 

[Donystoy]

You have to clear up the damper issues first to confirm that you have the correct air flow through the evaporator. Just like in your house, you would not try to charge up the A/C with a dirty air filter in the furnace. Also confirm that the hot water valve is functioning as it should. Had to replace mine last summer shortly before selling the vehicle. The screw holding the actuator to the valve disintegrated with corrosion allowing hot water to constantly circulate.

 

[Gumbel]

Hi Josef. Thanks for your reply. Can you clarify a few things, please... Which blend door are you referring to? Also, where exactly is the blend door located? Do I access the blend door from the cabin (behind the passenger side dash) or from under the hood near the firewall?

Since we're on the topic, there's actually a separate issue that I'm also working on. The air flow in the vents in the front row of the cabin blow very weak. After doing some research, I believe there's a door that is probably broken behind the passenger dash that is preventing the strong air flow.

The rear vents (controlled separately, I believe) has normal airflow, but the air is hot, even when the A/C is on.

I believe these are two separate issues - 1) weak air flow through front vents, and 2) hot air blowing throughout the cabin when the A/C is on

Lastly, about a month ago I replaced the heater blend door actuator because when I would change the temperature I would get the clicking noise. Replacing the heater blend door actuator fixed the clicking noise, and as I mentioned, now the A/C clutch turns on when I switch to A/C

The weak airflow Josef describes is a very common problem. The "fresh air/recirc" door literally falls off and blocks the fan intake. If it hasn't already happened on your 3rd Gen Explorer it will. The result is that you cannot shut off air coming from the outside, you cannot recirculate air for max A/C, and airflow to the fan is reduced by about 75%, reducing airflow at the vents and defog. Here's one way to fix it: How To: Repair A/C "Fresh Air/Recirc" Door You have to pull the dash. I followed what EyeintheSky57 did, except I did not have enough of the door pivot sticking through hole on the right side of the duct to drill a hole in the door arm and put a paperclip through. I drilled a hole on pivot arm to retain it on the actuator (left) side after it passed through the actuator. I also used some sealant to fix that pivot arm to the door so it wouldn't fall off again. The pivot arm clips into the door and invariable the plastic clip breaks. Horrible design. My fix made it through winter. Some people actually shove a t-shirt down the fresh air intake on the firewall side to block the outside air in the winter. Three 3rd Gens I examined at the junkyard had the exact same problem as did both of the '05s I had. I've also changed out a couple blend door actuators. Neither of these issues, fresh air/recirc door or the blend door actuator should be causing your lack of cold air problem unless somehow your installation of the blend door actuator is not allowing the blend door to go to the cold side. I don't know how that could happen, but I suppose it's possible.

 

[Josef161]

Hi Josef. Thanks for your reply. Can you clarify a few things, please... Which blend door are you referring to? Also, where exactly is the blend door located? Do I access the blend door from the cabin (behind the passenger side dash) or from under the hood near the firewall?

Since we're on the topic, there's actually a separate issue that I'm also working on. The air flow in the vents in the front row of the cabin blow very weak. After doing some research, I believe there's a door that is probably broken behind the passenger dash that is preventing the strong air flow.

The rear vents (controlled separately, I believe) has normal airflow, but the air is hot, even when the A/C is on.

I believe these are two separate issues - 1) weak air flow through front vents, and 2) hot air blowing throughout the cabin when the A/C is on

Lastly, about a month ago I replaced the heater blend door actuator because when I would change the temperature I would get the clicking noise. Replacing the heater blend door actuator fixed the clicking noise, and as I mentioned, now the A/C clutch turns on when I switch to A/C

Hi yes the blend door is in the cabin. You have to stick a 10" or longer stick in one of the vents. The correct vent is the leftern one in the center. Put the stick in the top right corner of that vent, it could fix your problems.

 

[h0op521]

Hi yes the blend door is in the cabin. You have to stick a 10" or longer stick in one of the vents. The correct vent is the leftern one in the center. Put the stick in the top right corner of that vent, it could fix your problems.

That worked. When I stick a long stick into the left-center vent, I get air flow through the front cabin vents. Here's a video showing that the motor is not responding to the air flow controls as I cycle throw all the different options from Max AC all the way through to defrost:

I also confirmed that my air recirc door is in tact, but it isn't responding to the air flow controls. Here's a video showing that the door is in tact:


So now I'm starting to think that I have an electrical problem, because both doors are intact but the respective motors are not responding to the air flow controls.

I guess it's possible that both motors are bad, or maybe there is a wiring issue that is effecting both motors. Is there a way to test the motors to see if the motors are bad - perhaps with a multimeter? Does anyone have an electrical wiring diagram to see how these two motors are connected?

Lastly, I'm still a little bit confused about how the air recirculation door works. What controls do I select to engage the air recirculation door?

 

[Gumbel]

That worked. When I stick a long stick into the left-center vent, I get air flow through the front cabin vents. Here's a video showing that the motor is not responding to the air flow controls as I cycle throw all the different options from Max AC all the way through to defrost:

I also confirmed that my air recirc door is in tact, but it isn't responding to the air flow controls. Here's a video showing that the door is in tact:


So now I'm starting to think that I have an electrical problem, because both doors are intact but the respective motors are not responding to the air flow controls.

I guess it's possible that both motors are bad, or maybe there is a wiring issue that is effecting both motors. Is there a way to test the motors to see if the motors are bad - perhaps with a multimeter? Does anyone have an electrical wiring diagram to see how these two motors are connected?

Lastly, I'm still a little bit confused about how the air recirculation door works. What controls do I select to engage the air recirculation door?

There are only two correct positions for the air recirc door and those are full open or full closed. The only positions on the dial that make the recirc door close are "off" (at the 12 o'clock) and max a/c. In any other position the door is open. It's a vacuum actuator, not electrical. The dial position causes the vacuum actuator to go either full up or full down which moves a crank-type arm that goes from the actuator to left upper side of the door. When the car is shut off, the vacuum actuator remains in the last position set on the dial which keeps the door either full closed or full open. From your video I can see that door is hanging where it's supposed to be (has not fallen over the fan intake) but is not connected to the actuator. I can also see that the actuator is not working IF the video shows you cycling through off, max A/C and the other positions. That arm coming out of the actuator should go up or down depending on what's selected. Check your vacuum line to the actuator and to the control panel. What is that zip tie attached to the actuator arm supposed to be doing? It looks like someone attempted to jury rig something to the door arm and it failed. Where that white zip ties is is where the end of the crank coming from the door is supposed to be. As the actuator goes up and down it moves the crank that moves the door. Your crank is not connected (thus your floppy door) AND your actuator does not appear to be going up and down.

Here's a picture of the actuator with the door crank arm in its correct place. You can see where the vacuum line attaches at the bottom. This crank is broken as many are. It's broken at the actuator side where there's supposed to be a piece plastic that help keep the crank attached to the actuator arm. I drilled a hole through that little piece going through actuator arm and pinned it place with a tiny cotter pin I made out of paper clip. You have a white zip tie going through the actuator arm where that little black plastic piece is supposed to be. The other end of that black plastic crank is supposed to clip into the left upper side of the door. It is broken too. The clip breaks. I glued it in place to the door with some sealant. It made it through winter working as it's supposed to.

 

[Josef161]

That worked. When I stick a long stick into the left-center vent, I get air flow through the front cabin vents. Here's a video showing that the motor is not responding to the air flow controls as I cycle throw all the different options from Max AC all the way through to defrost:

I also confirmed that my air recirc door is in tact, but it isn't responding to the air flow controls. Here's a video showing that the door is in tact:


So now I'm starting to think that I have an electrical problem, because both doors are intact but the respective motors are not responding to the air flow controls.

I guess it's possible that both motors are bad, or maybe there is a wiring issue that is effecting both motors. Is there a way to test the motors to see if the motors are bad - perhaps with a multimeter? Does anyone have an electrical wiring diagram to see how these two motors are connected?

Lastly, I'm still a little bit confused about how the air recirculation door works. What controls do I select to engage the air recirculation door?

Great that that works for now. Idk the think with the wooden stick is what i did for my explorer and I'm not fixing it as long as that works becausey explorer is 16 years old...

"also confirmed that my air recirc door is in tact, but it isn't responding to the air flow controls. Here's a video showing that the door is in tact:"

The recirc door can be uninstalled (then it would be open all the time) or fixated or glued to the closed position (then it will be closed all the time and you dont get the fumes from the truck in front of you).

 

[Gumbel]

There are only two correct positions for the air recirc door and those are full open or full closed. The only positions on the dial that make the recirc door close are "off" (at the 12 o'clock) and max a/c. In any other position the door is open. It's a vacuum actuator, not electrical. The dial position causes the vacuum actuator to go either full up or full down which moves a crank-type arm that goes from the actuator to left upper side of the door. When the car is shut off, the vacuum actuator remains in the last position set on the dial which keeps the door either full closed or full open. From your video I can see that door is hanging where it's supposed to be (has not fallen over the fan intake) but is not connected to the actuator. I can also see that the actuator is not working IF the video shows you cycling through off, max A/C and the other positions. That arm coming out of the actuator should go up or down depending on what's selected. Check your vacuum line to the actuator and to the control panel. What is that zip tie attached to the actuator arm supposed to be doing? It looks like someone attempted to jury rig something to the door arm and it failed. Where that white zip ties is is where the end of the crank coming from the door is supposed to be. As the actuator goes up and down it moves the crank that moves the door. Your crank is not connected (thus your floppy door) AND your actuator does not appear to be going up and down.View attachment 329156
Here's a picture of the actuator with the door crank arm in its correct place. You can see where the vacuum line attaches at the bottom. This crank is broken as many are. It's broken at the actuator side where there's supposed to be a piece plastic that help keep the crank attached to the actuator arm. I drilled a hole through that little piece going through actuator arm and pinned it place with a tiny cotter pin I made out of paper clip. You have a white zip tie going through the actuator arm where that little black plastic piece is supposed to be. The other end of that black plastic crank is supposed to clip into the left upper side of the door. It is broken too. The clip breaks. I glued it in place to the door with some sealant. It made it through winter working as it's supposed to.

I know this may not be clear. Your (black plastic) crank arm must still be connected to the door or the door would have fallen on the fan. However, your crank arm is not connected to the (metal) actuator arm. That's why your air recirc door is still hanging where it's supposed to be but it's hanging freely. If it was connected to the actuator it wouldn't be free. Someone tried to jury rig it with a zip tie, probably because the end of the black plastic crank arm where it connects to the actuator is broken. I don't know why your actuator arm isn't going up and down other than it's not getting vacuum. Those actuators are pretty reliable. You can pick up replacement pieces at a junkyard, but it's a lot of work to get at them.