This issue actually started late last summer, but once temps cooled it got put on the back burner.
Towards the end of last summer, it would take my truck's A/C compressor about 10 minutes to kick on after A/C had been selected on the control panel. Previously, the A/C would come on quickly and start cooling right away. When the issue cropped up randomly, the compressor wouldn't even try to engage until after 10 minutes. After the wait, it would work normally all day, unless I shut the truck off and let it sit for more than a few minutes, then I'd have to do the 10 minute (approx) wait again. I changed the serp belt that summer too as PM, but I can't remember if it was before or after the A/C issues started.
Stupidly, I assumed "hey, it must be low on freon after 10 years and a front collision." I got a cheap single gauge Wal-Mart recharge kit. Pressure did show a little low on the likely incorrect gauge, so I added the can until it got into the green zone for the outside temperature the gauge was set at.
Afterwards, the compressor still took 10 minutes to kick on, but also showed signs of probably being overcharged. When the compressor kicks on, it KICKS on, and the first engagement practically shakes the truck. After the initial engagement, it's smoother, but still not seamless like it used to be. Also, the engine is down on power with the compressor engaged whereas it used to be barely noticeable. Now you can feel the load when the A/C kicks on while going up a hill. This showed up right after the recharge and hasn't changed since, so it definitely seems like I overcharged it. Temps got cool so I left it alone, but now that we are getting into the nasty part of summer, I want to get the A/C fully back in order. Right now it still cools great, but only after its 10 minute wait and it's definitely working the engine once it's on.
Obviously the first step will be getting the pressure right. Probably just going to have a shop do a full evac and refill. I think now that I've put too much in, I can't legally get the pressure right even with a good manifold gauge set.
But that still leaves the 10 minute wait with the compressor. What could be going on there? Some sort of sensor? Worn out clutch? I would think a clutch problem would show up every time the compressor engages though, and not just cause an initial delay. Once on, the compressor seems to work fine and when running the A/C has always been very cold (never measured temp, but it cools off a black truck quick once engaged). This truck has a very basic A/C system operated with vacuum controls, no electronic control panel or anything.
Lesson learned on trying to fix A/C with a China kit from Wal-Mart. Probably would have avoided having to mess with the freon if I had tried to actually diagnose it or farm it out to someone else to diagnose last summer. At least now I know the 10 minute wait probably isn't related to the freon charge, but a good manifold gauge would have told me that.
Towards the end of last summer, it would take my truck's A/C compressor about 10 minutes to kick on after A/C had been selected on the control panel. Previously, the A/C would come on quickly and start cooling right away. When the issue cropped up randomly, the compressor wouldn't even try to engage until after 10 minutes. After the wait, it would work normally all day, unless I shut the truck off and let it sit for more than a few minutes, then I'd have to do the 10 minute (approx) wait again. I changed the serp belt that summer too as PM, but I can't remember if it was before or after the A/C issues started.
Stupidly, I assumed "hey, it must be low on freon after 10 years and a front collision." I got a cheap single gauge Wal-Mart recharge kit. Pressure did show a little low on the likely incorrect gauge, so I added the can until it got into the green zone for the outside temperature the gauge was set at.
Afterwards, the compressor still took 10 minutes to kick on, but also showed signs of probably being overcharged. When the compressor kicks on, it KICKS on, and the first engagement practically shakes the truck. After the initial engagement, it's smoother, but still not seamless like it used to be. Also, the engine is down on power with the compressor engaged whereas it used to be barely noticeable. Now you can feel the load when the A/C kicks on while going up a hill. This showed up right after the recharge and hasn't changed since, so it definitely seems like I overcharged it. Temps got cool so I left it alone, but now that we are getting into the nasty part of summer, I want to get the A/C fully back in order. Right now it still cools great, but only after its 10 minute wait and it's definitely working the engine once it's on.
Obviously the first step will be getting the pressure right. Probably just going to have a shop do a full evac and refill. I think now that I've put too much in, I can't legally get the pressure right even with a good manifold gauge set.
But that still leaves the 10 minute wait with the compressor. What could be going on there? Some sort of sensor? Worn out clutch? I would think a clutch problem would show up every time the compressor engages though, and not just cause an initial delay. Once on, the compressor seems to work fine and when running the A/C has always been very cold (never measured temp, but it cools off a black truck quick once engaged). This truck has a very basic A/C system operated with vacuum controls, no electronic control panel or anything.
Lesson learned on trying to fix A/C with a China kit from Wal-Mart. Probably would have avoided having to mess with the freon if I had tried to actually diagnose it or farm it out to someone else to diagnose last summer. At least now I know the 10 minute wait probably isn't related to the freon charge, but a good manifold gauge would have told me that.
