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Anytime the system is opened up or has a zero pressure it needs to be vacuumed to remove moisture. If you can't do it right it's cheaper to pay an expert.
Autozone was a good idea, but I think I will just buy a pump - they are a lot less than I thought they were. I have also read that Firestone will evacuate the 134a still in there for a small fee ($20?).
OK so the gauges got here. Readings look good. High side 280, low side 50. Everything seemed to be running fine, but the air temp coming out in the cab was only 68F after 5-10min. It is summer in FL, but that is not the 40F I believe I should expect with an instant reading thermometer stuck in a vent. Visual inspection of the condenser shows a few bugs but nothing major.
OK so the gauges got here. Readings look good. High side 280, low side 50. Everything seemed to be running fine, but the air temp coming out in the cab was only 68F after 5-10min. It is summer in FL, but that is not the 40F I believe I should expect with an instant reading thermometer stuck in a vent. Visual inspection of the condenser shows a few bugs but nothing major.
Need a little more info. Max AC (recirculation) or normal AC (all outside air)? Outside air temperature? What are you running the AC blower at? I assume high speed?
What is the engine fan speed? Sitting that long it should have gone to full lockup and running ~850-900rpm.
Side note: Learned something from Yahiko's tech manuals he posted. There is a dual fuction pressure switch/sensor on the high side. The PCM uses it to read actual high side pressure and will engage the fan clutch when needed. Explains why my fan isn't always running at high speed when idling with the AC running. It usually takes it a minute or two to kick in.
MAX a/c with recirc, full speed blower - the only way to run it in FL Outside is hot and sunny - 95F. Engine fan was whipping - not sure how to measure exactly but it was spinning fast. Bc the gauges were on, this was all just in the driveway. Thanks
MAX a/c with recirc, full speed blower - the only way to run it in FL Outside is hot and sunny - 95F. Engine fan was whipping - not sure how to measure exactly but it was spinning fast. Bc the gauges were on, this was all just in the driveway. Thanks
Pull up the FSS (fan speed sensor) on your Scangauge, Torque pro, Edge, whatever you use for engine monitoring.
Does the low side pressure hold steady? It's not dropping, cycling the compressor off, rising, cycling the compressor back on?
low pressure was holding steady. Took it for a drive. Lowest temp with max AC setting was 60F. Warmed to 70F when stopped. 20min ride around town. The Edge does not seem to monitor fan speed. Compressor seemed to be on the whole time.
Between the 95 & 01 Powerstrokes I have owned for like 30 years.... I had a intermitten problem like that and finally found out it was the connector running from compressor that plugs into high/low? pressure switch. I've replaced that connector four times over the years. If you are watching as someone above suggested.... reach over and wiggle the wires of that connector....if compressor clicks on or off... the connector needs to be replaced !
Get a temp right after the orifice tube going into the A/C box. you might have a door problem in the cab.
In the last few days, when I turn on the truck, the a/c comes out the defrost. I have to turn it off and then select the vents and turn it back on for it to come out the right way. I watched a powerstrokehelp video that says that the hinge on the door breaks. Apparently a real project to fix. I've been trying to run out the easy fixes that I could easily do myself. Beginning to wonder...
I am going to wiggle the high low temp switch first though.
Its been some time ago, but I remember reading a lot about that door problem when I was trying to figure out my problem. I think the door problem was with vacuum line... but I'm old, so my memory is bad...
The bad connector only involves the compressor turning on or off.... it would run fine until I hit a big bump...then turn to hot air... by accident I touched the wires... and realized there was a short.
And really...no kidding.... 4 times on the two PS trucks I have owned.
I have read about the vacuum line trouble with the door but supposedly that will prevent 4 wheel drive from kicking in as well. My 4 wheel drive is still working OK so maybe it is just a door hinge problem. It is weird bc on my long drive with lots of potholes, it seemed like the compressor was coming on and off, but now back home it seems to be working OK just not as cold as it should. A few year ago I took it in bc I did not think it was cold enough and they told me it was normal for FL so I don't feel like paying for that again.
From what I recall it's pretty easy to pull the glove box and the black plastic cover off the heater core to be able to see the blend door and make sure it's closing all the way. The actuator is easy to remove if it needs replacing.
If it's starting out in defrost you might have a slow vacuum leak. It should hold when the motor turns off. Grab a vacuum gauge and see what are getting.
One other thing to look at would be the evaporator it's self and see how dirty it is.
If it has a lot of crud in it then air flow will slow down.
On the blend door I think DieselTechRon may of done a video on how to replace it.
But it may of been someone else. Did not look all that bad to do. Just take your time.
07-13-2016, 04:37 PM
Outside is hot and sunny - 95F. Engine fan was whipping - not sure how to measure exactly but it was spinning fast. Bc the gauges were on, this was all just in the driveway. Thanks
