My '05 Expedition does not seem to cool as well as it used to. It has 60,000 miles and is in perfect shape and the a/c works but I am thinking it needs some refrigerant. Of course it could just be that the 105 daytime temps are just more than it wants to handle, but even when the sun goes down and it is only 90 outside it has a hard time keeping up.

I know my way around an engine but have never worked on a/c before. Is this a DIY project? I read Brady's thread but little was mentioned about the recharge itself.

It gets HOT here. 100 seems to be the norm and the hottest two months are still on the way so I am hoping it is low rather than just wimpy. We likely won't see more than a handfull of days under 90 for two or three months.

Prober, WELCOME to the warm side of WA!!!

Your temp estimates maybe a little high, but not too much. We usually have a couple of weeks where the temps range from 100-110, but then it cools off to a very comfortable 90's range for the rest of the summer.

Now, for you right coast guys and those of you who don't have coasts, those temps may sound hot but they're pretty decent. You're probably used to those temps accompanied by very high humidity.

Around here when it gets that hot the humidity is usually in the 35%-45% range. That makes all the difference in the world!

You're right about the humidity difference. I have found that 90 is very nice. I am not acclimated enough for much more than that though. In Seattle when it hits 80 it is very similar to 95 here since the humidity is usually around 70%.

You can add refrigerant yourself, but it can be difficult to determine how much to add without the training, knowledge and tools of the trade. The vehicles with a "sight glass" make it easier by simply adding until the fog clears up; but I don't know if they still use any of those in the newer systems.

I'm looking for a serious response, too.

Do those cheap refill containers from walmart with the gauges on them work well? They measure low pressure return?

I think they are OK as long as that is all you need.

A side note to this:
1. You may have a leak and will require adding again.
2. If the charge gets too low it cuts out the compressor making it more difficult to recharge.

It works...Works pretty good, especially when RPMS are up. It does not work as good as it has worked in years past. It's 14 years old, never been recharged.

That's my situation D-Rod. I don't think it works as well as it did a couple years ago.

It's hard to tell though since it gets so much hotter here and I mostly drive stoplight to stoplight.

Well, I checked the pressure today. It was about 38psi. So, appears as if I have plenty of freon.

My AC works great if the RPMS are over 1500. It's when the engine speed is down the air isn't as cold. I assume the compress is just aging and doesn't hold the pressure as well.

Your vehicle is 10 years newer, though. I wouldn't expect age to be a factor in yours!

Make sure the condenser ( the thing in front of the radiator) doesn't have a bunch of bent fins and is clean.
I used one of those do it yourself kits from WalMart, and it had a guage that told you how much you had in before you started. Seemed to work well.

Radiator was just replaced. The front is clean....

I have been a certified mechanic for (too) many years, EPA certified in A/C, also. These over-the-counter kits can be used successfully, if low refrigerant from minute leaks is the problem. They can also do as much harm as good, as overcharging a system that has other problems is a bad thing, at the very least you will waste your time and effort.
Many things come into play when looking at A/C pressure, such as ambient temperature, humidity, etc. The pressures, both high and low side, will give an indication, but it is impossible to say that a certain pressure is right or wrong. Incorrect procedures introduce moisture and air into the system, causing other problems, also
You are actually sometimes better off flying by the seat of your pants: if it feels cold, it is. The average car or SUV holds only about 2-3 lbs. of Freon, a regular cab pickup even less.
Two old sayings come to mind: 'Ignorance is bliss', and 'A little knowledhge is dangerous;.
Read the directions, and good luck!

I've used the Walmart/Pepboys products with some pretty good success over the years. Those kits now come with gauges built in, so it's pretty easy. Some of them have dye and/or sealant in them to help identify/plug small leaks.

this is a funny conversation..

Use the wal mart, store bought can with the charge hose and gauge attached.

get the 134a with leak sealer in it.

hook it up to the low side, turn the AC on high, fan on high speed, put a thermometer in one of the vents, measure the temp and wait for it to stablize. Your discharge temp should be somewhere around 50* or less depending on the load.

To locate the low side charge line, turn the AC on and feel for the "colder" of the two lines then find the red or black dust cap. (thats where you hook the gas up)


If all else fails and you havent pi$$ed him off , you can email CNY for a little advice. he helped me and I am nothing but grateful!!

CNY helping me out.

Thanks Brady, and all who posted. Seems simple enough. Iactually think it's OK justthe outside temp is so hot that it takes a while at higher than idle speeds to get things cooled down. It works much better when the outside temp is 90 or less and I suspect that a few minutes at highway speed will make a difference as well.

I will know more tommorow as I have to drive a couple hours away.