2000 v10. need some help from the AC gurus here.

last summer the AC worked adequately. this year not so much. did not ever see the infamous "dump" out of the back end. No issues with front or rear units blowing hot when on cold. AC is blowing "cool" air currently (front and back are the same temp). Cool = lower than ambient temp but not any where near cold. compressor looks to be operating and engaging properly with no strange noises. ac pipes get hold and "cool". i have condensation dripping from the back compressor as normal. both condenser and evap coils are clean. The compressor is engaging off and on regularly at 2 seconds on and 8 seconds off.

I figure that the system most likely has a leak so i get some AC Pro with UV stuff to add coolant and find the leak. I purchased the can of r134 and the hose/gauge separately. Put the two together and plugged it into the low pressure side. Cranked up the motor with Max AC on blast and tried to add the r134. the gauge reading was going up and down as the compressor turned on and off. The pressure readings were in the green with compressor engaged and then it dropped to white when the compressor turned off and was zero when i squeezed the trigger. I followed the instructions and watched several videos and even weighed the can of r134. the can did not get cold, make any noise, loose any weight and my AC did not start blowing colder. After several attempts to add r134 i figured that because the compressor was only on for 2 seconds that it might not be drawing in any new refrigerant. so i jumped the low pressure switch to keep the compressor engaged and tried again. no joy. i am at a loss as to what to do now other than take it in to ford and pay out the nose to get it figured out. I did notice that when I shut off the motor i can hear a hissing sound coming from the dryer/accumulator area. not sure if that is normal or not...

so i am guessing i either something on my ex is broken or maybe my new r134 can/hose is bad or the cap didnt puncture the can? does that happen? i am afraid to take it apart as it is pressurized...

TIA

 

 

 

maybe someone else did that repeatedly and has over 25oz of oil in the system.....this was my problem, previous owners who half **** everything suck.

get a real set of manifold gauges

 

 

There is most likely air in the system yes, but probably not to the extent already listed. At this point you may be over charged with oil, and you may have a poor refrigerant line tap. My Ford is OK, but on one of my Chevy Astro service vans, I need to clamp my charge hose adapter to the refrigerant line so it will properly engage/depress the schrader core. Air and moisture are both "non-condensables", and typically migrate to the condenser. I can't tell you with exactness on the Excursions, but standard safety equipment on an A/C system will include a high pressure cut-out, (if over pressure), a low pressure cut-out for (low pressure) situations, as you have already become aware of, and sometimes a high pressure blow off to simply relieve the high pressure.
The most important thing you need, if you are doing to do this yourself, is a proper set of gauges, rated for 134A.
When you go to the doctor, the first thing they do is triage you, the same needs to happen with your A/C, especially if you are not the original owner and do not know the history.
Your pressures, both low and high will tell you a lot about the system. Since you seem to be short cycling, you are most likely low on refrigerant, the leak dye is instrumental to have in there, but for a leaky service port, which could be your culprit, not so much. A quality electronic leak detector, or soap bubble leak detector will help you with the service ports, while the leak dye is great for the evaporators, and O ringed connections.

 

So it turns out that all new cans of r134 made in 2018 have to be self sealing. The can I have is a self sealing can but that is not listed on the can label any where or in the instructions. I called AC Pro and they told me I need to go buy an adapter to use with the hose I have. So I will be getting one tomorrow....

 

I just want to add a little r134 with the UV dye to try and identify any potential leaks. Not trying to bandaid my system here, just diagnose/ fix myself if possible. Next step is either get the full guage/pump to evacuate and recharge myself or take it in. Local dealer wants $200 just for diagnostics/evac plus $$ for new r134 and Jiffy lube quoted me at $80 to evacuate and then $40/lb. for r134....Haven't called around to anywhere else....

 

i think i spent 160 on mine at a local shop that was for evacuate/testing/4.5lbs of r134a. the Ex is definitely not a small system!

 

I just had mine done at a Valvoline oil changing place after my body off head stud install. It was about $120. They check for leaks and fill.

 

If you do not already own the stuff to do it, vaccum pump, a real set of 134a gauges, a bottle to draw the refrigerant into using the vac... just have jiffy lube, or another shop, do it for the $120'ish.

A good vac pump will cost more then the shop doing it, and if i recall correctly a decent set of 134a gauges new is around $80.

 

Update. Got 2 cans of r134 into the system. Air temp from the vent was 49. outside was reading at 80. So the system was low. Took a uv light to everywhere I had access to without taking off panels and didn't see any trace of a leak. I did see some uv reflective stuff on the bottom of the compressor....so I may be in the market for a replacement in the near future....what I did see was dry, possibly from the first can a few days ago? Nothing looks wet....Does anyone know if the leak stop these cans boast about actually works? I am going to give it a few more days in this 90 degree heat and drive the ex around and see what happens with the compressor...