I'll start by saying that I've done a few Advanced Searches to resolve this problem, but so far - I've still got it. The compressor clicks on and off frequently which might suggest low refrigerant. I bought a recharge kit and did the work, and while the can is attached, the compressor is quiet. However, once the can is removed, it's not long before the clicking begins again. Although the dial gage on the recharge kit from WalMart is not a calibrated device, it reasonably suggests that I have a full charge (around 45). Also, when I set the dial to AC, the time between cycles goes from 5 seconds to 25 seconds as I continue to drive. If I put the dial to Max AC, the interval is again at about 5 seconds (same for Deforst settings). The air blows cold even on the hot days, so I'm not guessing I have a leak. However, I wonder given that the system seems to behave properly when the refrigerant can is attached. I know that they have dies that can be used to detect leaks, but I was wondering if it was worth it (e.g. would it find a leak I need a pro for anyway). One of our fellow FTE colleagues suggested that it might be the compressor clutch switch. With that said, I wanted additional input as to what it might be and any recommendations.

Thanks in advance!!

Kevin

 

Is this truck new to you?
I bought my 2000 new in 2000 and that's how my AC worked from day one and still does with 160,000 miles on it today

 

Not really an AC man, but it sounds like it might be the compressor clutch re-lay. Hopefully someone will more knowledge will chime in. Good luck.

 

Greenpus: I also bought my 2000 new and my AC never ran like that. Have you ever had an expert look at it? Now you kinda have me wondering. Thanks.

 

Nope. It has always blown cold air so as far as I'm concerned it works

 

You might want to read the FAQs in the HVAC section. The A/C system is fundamentally the same on the Ranger as on the larger trucks.

 

Go take it to a pro, have them hook up their machine. They can test the system, evac and recharge, and put a dye to see if and where the leak is. If you keep fooling with this yourself without proper knowledge of the AC system you will do more harm that good. If you let the pros fix it before something fails, it will actually save you money. Those stupid DIY kits are an AC system failure in a bottle.

 

My 2000 does the same thing, A/C works great as does the defrost even though it has 185K on it. The clicking noise gets annoying when it is at idle.

 

the only time i really notice the clicking is when I'm sitting at the drive up window at mcdonalds waiting for my hamburger

 

Thanks for the input folks. The compressor clicking on and off as rapidly these days is new to me, but not the truck. It blows cold air (will condense on the rear window) into the 80s, so in all other respects, it seems to be working correctly. As Greenpus puts it, it's most noticable while waiting for food at the drive-thru or in traffic waiting on a light to change. My concern is that if it cycles this much, it may cause something else to fail eventually...and would lead to a more expensive repair.

As with the Advance Searches I performed, the vote here seems split as to whether or not the rapid toggling on and off is normal. The Ford tech I spoke with a few weeks ago was banking on a low charge, but didn't seem to me to be overly concerned with the frequency of change. I'm not there knowing it was a longer interval not too long ago. However, my power steering pump whines and when I speak with folks on this point, most just think it's a characteristic of a Ford product (whines, but otherwise just fine). Put the front end on jackstands though, and the whining goes away. So, maybe they're right, but maybe they aren't. Two mysteries I'd like to solve though for piece of mind. But AC first and then I'll do a deeper dive on the powersteering pump whine.

Regards,

Kevin

 

My PS has always whined or made a noise when turning the wheel. I drained the PS fluid with a turkey baster and refilled with synthetic Redline D4 ATF. It helps to put a short rubber hose on the end of the turkey baster so you get it all. I start this process by driving the truck until it hot and then drain the PS. I drive the truck to work for about a week and on the last trip home I again drain the PS and refill with ATF. I do this 3 or 4 times and my assumption is I get most of the old fluid out. After doing this I noticed my pump was a little more quit with the syn atf. Ford recommends MERCON ATF for the PS and Redline D4 ATF is MERCON compatible and I also put it in my manual tranny.

 

Thanks Greenpus. I did something similar and even added an additive that supposed to quiet the pump. Not sure if it got quieter or not, but when on the stands, no noise. A friend suggested that at as the factory sealed moving/joint parts age, they dry out and put more strain on the pump hence more whine. I had the ball joints replace a month ago and fresh grease put in, but still no improvement. The common theme for the autoparts folks I asked about the whining pump: they point outside to their business Ranger and say that it does the same thing. Most have over 200K miles on their original pumps to and most figure it's been there from the start. That said, I found a thread with a recipe for quieter PS pumps here (using Seafoam which I couldn't find locally). Once I find the Seafoam, I'll follow the recipe and see what it cooks up.

 

The compressor I believe cycles on the pressure in the vapor side of the refrigerant system. There is a direct correlation between pressure and temperature (IE: a certain pressure of a known refrigerant, R134a, = a specified temperature). So in order to keep the evaporator at a specified temperature, they use a pressure cycling switch. If you are cooling, and the pressure is 45 psi (which = 49 degrees F), you could have a failing pressure switch. That is where I would look first. I have never changed one on a Ranger so I don't know if there is a Schrader valve under it or not. If not, you will have to recover the refrigerant from the system first, change the switch, then pull a vacuum on the system, and weigh in the correct charge.

Hope that gives you a place to start.

 

I am no auto a/c expert,but I have a idea. Check for a loose electrical connection at the compressor clutch and low pressure switch (if you have one it would be on the bigger line. If there is a high pressure switch on the smaller line, check that too).

Do you have a compressor relay if the power distribution box (look in owners manual)? If so, and it's the same as a fuel pump relay (for example) swap it out and see what happens.

Anything other than that, take it to a shop. Liquid refrigerant spraying on your skin will give you the worst kind of frostbite. You will be in the hospital in a lot of pain (never happened to me but I have seen pictures of the damage).

 

sounds to me, like the pressure switch is either failing or is out of adjustment(if it is adjustable like my 88's is.)

"Those stupid DIY kits are an AC system failure in a bottle."

funny.. i used one on my '88, and it's been blowing nice and cold since 2001....in the 100+ Phoenix summer heat no less..only problem it has is the compressor shaft seal has a small leak..(greasy dirt between the pulley and the compressor itself) and that was not caused by the DIY kit. who knows how old the compressor is, since i pulled it from the junkyard.. the pro's overcharge for their services, that is why i don't take my A/C problems to them..i bought my own guage set, and vac. pump..and do my own work. I wanted to replace the A/C hoses on my old 1990 F250 when i used to have it.. the shop wanted $75.00 per HOUR to rebuild the hoses and that it would take min. 2 hours... i said forget it, i can buy new ones at Autozone for $100..they also wanted some godlike amount for a REMAN'd compressor..
with all of the stories i've heard of shady shops around here, i don't take any of my vehicles to any shop, except for my 2011 F350 which has to go to the dealer because of the warranty.. once warranty is up, i'll do my own work.
another example of the pro's and how they work is, I had a friend with an 02 dodge truck.. a/c shop gave her a bunch of BS and wanted to charge her $1500 for a new compressor and a bunch of other junk..she had me look at it.. turns out the condenser fan(dodge has the condenser off to the side of the radiator with it's own elec. fan) was seized up and not working.. about $120 for the new elec. fan and some work later, I had her A/C blowing ice cold again..

if you do decide to go with a pro, get at least 3 opinions.. because alot of these A/C shops are shysters..