cleaning evap core still in the vehicle?

[DSG2003Mach1]

my 12' f150 is having some ac issues. Schrader valves were leaking, replaced the expansion valve and the dryer/orifice tube. Cooling way better than it was. The shop sent screen shots of the data showing the evap core is getting down to 37 degrees but out of the vents was in the low 50s. They're claiming it must be a restriction through the evap core. The fan motor is relatively new motorcraft.

Im not paying them $2500 to replace it and not looking forward to a full weekend to yank the dash. Anyone had luck cleaning an evap core up any still in the vehicle? My dog rides along ALL the time and it's always on recirc so wondering if it isnt full of dog hair (no cabin filter on these trucks).

I was planning to see if I can get my inspection camera up the vent from the fan and look around. I've seen various posts and youtube of videos of people sending vacuum lines up the duct from the fan or removing the air bag/glove box and cutting an access panel to get in there as well. Obviously cutting a panel is the biggest risk to really screwing something up.

Just wondering if anyone's done it with any success since it's not leaking.

 

[Crimson2v]

Did they give you any pressure readings to back the claim of having a restriction in the system?

 

[DSG2003Mach1]

Did they give you any pressure readings to back the claim of having a restriction in the system?

Im 99% sure theyre talking about air flow across it, not in the refrigerant lines. My understanding is the evap core should be 36-38 degrees and its reporting back 37 but vent temps arent what you'd expect based on that.

 

[Crimson2v]

Im 99% sure theyre talking about air flow across it, not in the refrigerant lines. My understanding is the evap core should be 36-38 degrees and its reporting back 37 but vent temps arent what you'd expect based on that.

Is your airflow out of the vents not blowing as it should? If the core is stopped up with dirt it affects airflow not temp. It will still be cold out of the vent just barely will blow however.

 

[365 Saleen]

My guess is that you have a blend door that is not closing all the way thus allowing some of the air meant for the evap core to be going past the heater core.
Sometimes the blend door motors get worn and don't have the range of travel that they are supposed to. Or the blend door pivot or hinge gets worn out and will not let the door close properly. In extreme cases it is the whole HVAC box that has to be replaced.

 

[Crimson2v]

My guess is that you have a blend door that is not closing all the way thus allowing some of the air meant for the evap core to be going past the heater core.
Sometimes the blend door motors get worn and don't have the range of travel that they are supposed to. Or the blend door pivot or hinge gets worn out and will not let the door close properly. In extreme cases it is the whole HVAC box that has to be replaced.

Bingo.

 

[2011 gtcs]

A scan tool should show what the servo motor percentage is and what spec should be. The tech should be able to see that. But if you're looking to clean your evap core, get something like this
Genuine Toyota Parts - Ac Refresher Kit (00289-ACRKT) https://a.co/d/j6cO8Sd

I would still ask the tech to verify your A/C servo motors are operating within spec, any decent diagnostic scan tool should be able to do that.

 

[DSG2003Mach1]

According to forscan and the tool the tech used the blend doors are working correctly (mine has 3 or 4) Assuming it’s actually doing what it think it’s doing. I’ve thought about just replacing them all since it’s like $100 in parts

I don’t really think the air velocity is correct on max ac setting.

Oreilly has foaming coil cleaner on hand. Like I said I’ll check it with my inspection camera first.

 

[svtfocus2cobra]

To answer your initial question, yes, in some cases flushing the lines does work. It's worth trying before you pull the dash to get to the core. One of the shops I worked at had a nozzle that worked really well for it but there probably a number of products out there that would work.

 

[Bullitt1448]

According to forscan and the tool the tech used the blend doors are working correctly (mine has 3 or 4) Assuming it’s actually doing what it think it’s doing. I’ve thought about just replacing them all since it’s like $100 in parts

I don’t really think the air velocity is correct on max ac setting.

Oreilly has foaming coil cleaner on hand. Like I said I’ll check it with my inspection camera first.

The inspection camera is the hot ticket before spending a weekend pulling the dash re and re and ending up with rattles. It might not save you if the core is plugged up but it just might too.

 

[hotcobra03]

Adobe Acrobat

acrobat.adobe.com

 

[hotcobra03]

Adobe Acrobat

acrobat.adobe.com

 

[hotcobra03]

2 section on ac.

Depending on type of system will determine diagnostic steps.

So much junk for a simple task.

 

[DSG2003Mach1]

2 section on ac.

Depending on type of system will determine diagnostic steps.

So much junk for a simple task.

thanks

i finally got my info straight - this truck has 4 blend motors (digital dual zone)

YH1933 - temp blend door for driver (down under the dash and pain in the ass but there are videos on replacing without removing the dash or center console), pass side is behind the radio. I have had a forscan short to battery ground code once for the driver side motor but my thermometer is showing the same vent temps on driver and pass side, so not convinced this is a/the problem

YH1770 - recirculation control - pretty sure this is in the pass side behind the dash. I would say this one might be questionable, if not operating properly it might not be 100% recirculated air

YH1881 - vent selection - defrost, panel, feet etc. This seems to work fine, on max air only comes out the main dash vents so I think this is fine.

current plan of attack is to yank the pass side air bag, replace the recirc motor, inspect the door itself since apparently they tend to break. Then I'll inspect the evap core itself, even if it means drilling some holes or opening up an access panel. Time permitting I'll inspect/clean out the fresh air stuff (requires pcm removal) as Im sure it's full of leaves and such just like the area behind the wheel well liners


The repairs performed by the shop got actual refrigerant pressures to proper range, compressor is cycling as expected and evap core temp is reporting back at 37 degrees as expected.

 

[hotcobra03]

Adobe Acrobat

acrobat.adobe.com

Read this. Last 2 steps are how to reset blend doors.

 

[hotcobra03]

Adobe Acrobat

acrobat.adobe.com

Left side

 

[DSG2003Mach1]

Adobe Acrobat

acrobat.adobe.com

Left side

shit cracks me up - remove evap core like it isnt a 10+ hour job to R&R.

luckily there are videos on how to get around this - you remove the center console if so equipped and it can be done from the driver side foot well.

the defrost mode one is easy, minus just being in awkward space.

do you have one for the fresh air/recirc motor? I think it might say to remove the core as well but its apparently doable with the pass side air bag, panel on the end of the dash and trim covering the fuse panel removed.

 

[DSG2003Mach1]

Took the fan motor out and recirc motor. Blend door is moving just fine, replacing the motor since it would report back “error” when moving to the recirc position. I don’t think it was moving ALL the way to sealed off though based on clocking of the gear ans how it felt when I moved it.

Bad news is the evap core is CAKED in dog hair since there’s no cabin air filter

 

[Crimson2v]

Took the fan motor out and recirc motor. Blend door is moving just fine, replacing the motor since it would report back “error” when moving to the recirc position. I don’t think it was moving ALL the way to sealed off though based on clocking of the gear ans how it felt when I moved it.

Bad news is the evap core is CAKED in dog hair since there’s no cabin air filter

They aren’t too bad to remove. You can have the core replaced in a day.

 

[DSG2003Mach1]

They aren’t too bad to remove. You can have the core replaced in a day.

Ya but for **** sake I don’t wanna mess with it if I don’t have to…. Pulling the damn center console and all that.

My motivation to complete projects like this certainly isn’t what it used to be. If I have the shop do it it’s expensive but also a 5 year 50k mile warranty

I’m gonna try drilling some 1/2” holes and use this shop vac extension and see how it works or maybe just cut a big panel out and clean it.