Foxbody Mustang Air Conditioning Full Overview & TIPS

[@Mustang5L5]

I have some NOS motorcraft lines and such I picked up years ago before they were discontinued. All still factory capped and sealed on the ends. For the hell of it I decided to pop the caps off and blow through them (4 total), and all of them have equal restriction in it. I can definitely blow through them, but nowhere near as fast as the good line in the video does.

[@ogsuperflygarage]

Chris...I really enjoyed this video and the comprehensive explanation of the Foxbody AC system! Well done!

[@chrisarnold769]

I am literally fighting this, right now. I replaced the liquid line from LMR and I'm getting right at 20psi low with 275+ high... Air is blowing 50-60* in the car. Think I'll order up another liquid line. Thanks for your help, Here's mine: use a pick (dental or small with right-angle) to lightly run inside the spring, pushing it out, and then when you go to push in the spring tool, use it again to get the lip inside of the spring before pushing the rest of the way in. Makes this much simpler than the way more fight and struggle to get inside of the spring.

[@adamcartwright6220]

Great video!! Thank you! Thats the best understanding of a Foxbody AC system I’ve ever seen on KZbin! Thanks Chris!

[@TheInfamousProject]

I appreciate it. I am no expert but I have learned a lot in the past little while and figured I would share before I forget.

[@devinsplaylist7]

Man another crap ass part from LMR. I’m not knocking the company I’ve bought a bunch of stuff from them and their customer service is great but they need to start weeding out some of these cheap ass parts. I’ve had to re-do countless jobs because of them and that’s the reason a lot of people give up on Foxbody cars all together. Thanks for another great video. fixing my AC is one of the things on my to-do list. Your knowledge and willingness to share it is one of the things that keeps me going. 🤙

[@Joeshomegarage]

@@devinsplaylist7 I ordered my new parts from rock auto and I've had the same problem. Just removed that line last night and can barely blow through it. Got a new one from Amazon and it's more free flowing. Everything was brand new except the evaporator so I believe the line was bad from the start. Annoying BS Chinese parts🤣 should have left all the stock stuff it worked someone just ran 12v to the compressor to bypass the pressure switch.

[@DCHutchins]

Not sure about the quality aspect, but I have to give LMR credit for helpful videos along with this channel and other. I got my 89 new and I still look at the LMR channel and have my stack of Fox body and Ford ECU books to remind me of stuff.

[@Joeshomegarage]

@@DCHutchins it's hit or miss from every company. LMR doesn't make the part. I ordered one from rock auto and it's blocked ordered a new one off Amazon it seems good to go. I don't want to look but I've probably spent 5k to 6k with lmr this year 😳🤣

[@mikejackson6941]

I have the same issue with my new complete kit.

[@steamy1225]

So, looks like Chuck is from MI like me. Great info on the AC. Thanks, I have an 88 Stang LX and still have the original AC components on it and still charged with R12. Blows cold . I did change the heater core a while back but not the evap as the system was still charged with R12 and don't have a machine at home to recover or recharge the ac. had my car since Feb 2nd 1993.

[@AJsSpeedShop]

Thanks for posting this! Very informative. I’m troubleshooting my AC down here in Houston right now as well. I can only get upper 50*s vent temps on 93* days so I’m going through the trouble checks myself. This is my first foxbody so your demo really helps!

[@AwakeDude911]

brand new PARTS in 2024 is not the same BRAND NEW PARTS in 1987 1988 to about the year 2000 .. parts today are delivered broke in the box or messed up...back in the day i never remember getting a BAD PART

[@devinsplaylist7]

You are 100% right. The parts these days are terrible

[@robertwalker8052]

current performance wiring makes a module thats plug and play with terminator x and a pressure switch, got mine blowing cold super easy install

[@347svtcobra]

I appreciate this video I have a 95 Cobra someone felt the need to remove the ac from in Georgia and FTO SUCKED without ac gonna be ordering everything from lmr soon after watching this

[@nunya2814]

Ive always had the thought, if you cant get cold air in your fox using 134a, your doing something wrong. I just did a customers 87gt vert, only had 43k original miles but the compressor and all the lines were leaking. I replaced lines and compressor,flushed the evap and condenser, vac down the system, used 1.5 lbs, system would blow 34°f air out of the vents, so cold my customer said he only runs the fan on the first or second setting and were in FL.

[@imacarguy27]

Man I can't thank you enough for making the AC video you just made. Id been chasing my tail since last summer on the AC in my SSP. First I had an intermittent air gap on my compressor clutch causing intermittent engagement. fixed that. then I put a new receiver dryer/low side line and a new liquid line in. the liquid line would freeze but the AC fucking sucked. I noticed my low side was dipping down to like 15 ps and would only climb back up to like 30psi when the compressor was switched off. my compressor was cycling on and off every 3-5 seconds. Tried messing with the low pressure switch adjustment screw. Tried messing with r134 weight. nothing was helping. I was even starting to suspect the condenser was causing a restriction. But I saw your video, said fuck it and went and bought another liquid line. And holy fuck, my AC is blowing icicles. The ride home from my shop I had to actually turn my fan speed down cuz it was getting really cold. of course this happens the day before my car goes in for paint so I can't enjoy it for a few more weeks. thanks again man! you're a real one for pointing out the shitty clogged brand new orifice tubes. 🤝

[@Joeshomegarage]

@@imacarguy27 awesome! Mine was doing the same thing chris's was doing blew the top line twice. Wasn't seated all the way then blew the relief valve and I walked away from it. Just pulled off the liquid line last night and can barely blow through it. New line is a lot less restrictive so hopefully that solves it🙄

[@RedHammerBodyShop]

Thanks Chris, this video is going to help a lot of folks.

[@clemmahabir]

When I bought my foxbody, the AC system was removed already , and also the hoses to the heater core. My Mustang is a convertible and only summer driven. I still have the original AC compressor and the lines and condenser. Makes me wonder why it was removed probably stopped working altogether. I'm not gonna install it back because it's not cheap to send it to a shop. I usually have the top down and avoid really hot days and never drive in the rain, and stored in the winter up here in Canada. Last year my Lincoln town car had a leak in the AC system, my mechanic had a hard time finding the leak after a couple attemps and wasn't cheap to repair, but you need AC in a black car, summers up here can get really hot!

[@Joeshomegarage]

Dealing with this exact same situation. Everything is brand new and I've blown that line off twice at the condenser because it wasn't seated all the way and then once I got it on properly it keeps blowing the relief valve. So frustrated I walked away from the car a month ago. I did order a new line, new relay pigtail and the proper wot relay. I'm going to try again today and if everything is clear I'll take it to the shop for a proper charge.

[@inerceptor]

WOT relay is what gave me hell. The previous owner of my car had removed everything and cut wires too. I had to rewire and trouble shoot everything.

[@jamesrene9378]

lol the heat makes you look a lot older 😮

[@jessemas27]

Holy crap! That's why my trunk release doesn't work on my coyote swap. Open circuit. That has been so annoying.

[@chuckp7970]

Excellent, informative video. Defintiely gave me a better understanding of the A/C system. Sorry that the car, like its owner, has been a pain in the ass. LOL! 😂 But I can say I'm at peace with the build being done now that the Burrberry blanket has been used on the car! 🤣🤣🤣

[@TheInfamousProject]

LMFAO

[@Notatroll4207]

Im going throught it too same dam thing thank you so much chris

[@D1ggity75]

Amazing video/subject! Thank you for putting this together.

[@Joeshomegarage]

I'm hoping this is my issue. I ordered the disconnect tool and broke it trying to get the line out of the evaporator. Ended up using half of a hose clamp. I can barely blow through the line and the new line is much easier to blow through. I ran into the scoop issue on the lines at the compressor and I have all new parts. I ended up ordering the compressor fittings from LMR and they don't have the scoops in them. I was going to cut the lines back but figured it would leak. So tired of this damn AC. Wiring was all F'd up too🙄

[@TheInfamousProject]

Good luck man, let me know how you make out

[@Joeshomegarage]

@@TheInfamousProject Thanks Chris! After having the top condenser line blow off twice and then the relief blow a few times I walked away and it's been sitting for a month. Black notch curse with no AC and no tint yet no go for me🤣 your video and the pod got me motivated again! 👍

[@charliebruceortega8447]

Good info, that black lx hatch looks bad ass

[@williamjones8283]

Is there not a way to remove the old line clear it out, and reuse it?

[@josesanchezgearhead2013]

Can you cut the orfice out to see the problem?

[@walterm9300]

Hey Chris did you flush the Mineral oil out. And replace with PAG oil before charging with 134-a ?

[@tstelogeannis]

I have all new R134 parts for my 1990. It dies off at acceleration. But comes back to cold. Whats up?

[@RedHammerBodyShop]

I just ordered EVERYTHING new so now I'm worried. Lol

[@MrLocomechanic]

So the compressor isn’t suppose to cycle off and on to regulate pressure? I could have swore it’s supposed to on these older systems. I have a problem where mine is staying on constantly and doesn’t seem to be cooling down all the way.

[@Mustang5L5]

No. The only thing that turns the compressor off is when the low-side pressure drops far enough that the low pressure switch opens, which cuts off the compressor. With R12 this switch is set to 25psi. With R134a it should be adjusted (there's a screw if you look down between the terminals) to turn off the compressor around 21psi. Ambient temp will play a huge roll in system pressures, and on a hot humid day the compressor should barely cycle. If it's a much cooler day, the pressures will be lower so there is a chance to hit the low pressure cutoff. Premature cycling is also another sign of inadequate refrigerant levels. Really you need to hook up a set of manifold gauges with a high and low pressure gauge to get a full understanding as to what is going on. A compressor that's cycling a lot may have a blockage in the orifice and you'll see this with an extremely high pressure on the high side and the low pressure side falling way off under the pressure cutoff.

[@MrLocomechanic]

@@Mustang5L5 mine is close to full on the gauges per temp outside but it just stays engaged constantly. I could have swore years ago the compressor actually cycled off and on and caused the system to build enough pressure to cool properly. As for new systems the compressor stays engaged but the system cycles it a different way. Like you’re supposed to do the gauges go up and down where as what I’m seeing is a steady pressure and no fluctuations

[@Mustang5L5]

@@MrLocomechanic yeah the new systems are variable displacement so they operate differently. But on a fox, it’s just the low pressure cutoff. I redid my system about 4 years ago and on a hot humid day, the compressor very rarely cycles if at all. I get 35-39 degree vent temps at idle, but I’m running R-12. Honestly, if your compressor is always on, and cooling is inadequate, it might be possible the orifice is too open and you do not have adequate pressure drop. Only way to tell this is to hook up manifold gauges and see what your high and low side is? High side should be 2.25-2.5x the ambient temp. Low side should be in the 25-35 range. General rule of thumb.

[@sublime929]

Hahaha I literally laughed out loud at the cringed face when you said "LS swap".

[@Stanggt8587]

Great Video!

[@dennish9519]

Not sure why I am watching this cause my foxbody is a Factory non-A/C.

[@fmann5th]

Thar beard tho lmao

[@AwakeDude911]

30:00 that's why hoarders are useful in 2024 and beyond ...they called gramps a KOOK now they say hey can i buy that rusted out foxbody from you for a few grand (when back in the day nobody gave scrape prices you just found a place any place so it wouldn't cost money out of YOUR pocket to dump it)