I have a 2004 V6 4.0 Ranger just purchased used in the last three weeks. At time of test drive the AC worked perfect. Cold as all hell. Had to turn it way down, in fact.

The other day I had no cold air. Temp outside was maybe 80 and inside it was 70+ at the middle vent.

With the truck sitting in my carport at idle and at around 2K the compressor cycles on and off. Mostly it is off. I have only a simple push on pressure gauge but here is what I'm seeing at the low side (#2 in the diagram below). If I hold the gauge on and keep the reset pressed in it will allow the needle to move. It goes from around 20psi when the compressor is running up to around 60psi when the compressor stops rotating.

Any suggestions as what to check/test will be greatly appreciated.

I'm hoping this dealer did not top off the coolant knowing there was a leak just to sell the truck but who knows.

Found this diagram which seems to match what I have. If we can use this for replies, it will make it easier for me to follow you.

https://www.ford-trucks.com/forums/a...ntid=497&stc=1

 

I'm fairly certain there is a leak in the system. Assume it was there all along but I cannot prove that now.

So here is where I'm at.

1) I can invest in a can of UV leak dye and add to the system and try to locate the leak. Crossing my fingers it is not the compressor.

or

2) I can buy a can of leak stop and add that. Then, try recharging the system to spec (33 oz according to the label on the car) and see if it holds.

Doing the #1 will require a full repair. That means taking the truck to an AC repair facility for evacuation/recovery, replacing what is leaking, replacing the accumulator/dryer and recharging the system. If they will only do the recovery for me I can do the rest by renting the tools at Auto Zone. If they will not then I have to pay them for the work.

What do you folks suggest?

 

Sorry to be replying to my own posting but as I find out more...

This product has some very favorable reviews on Youtube so I may just give this a try. It is an all in one deal. Has UV dye and some refrigerant but the main reason for using it is its ability to repair most all leaks... other than with the compressor.

BlueDevil Products Red Angel 00222 - A/C Stop Leak & Conditioner | O'Reilly Auto Parts

They offer a 30 day money back warranty and claim it will not clod system so not much to lose, here.

Comments?

 

Not up to speed on AC, but if I had to guess those "leak fix in a can" are probably not well received by mechanics. Maybe they will work OK with a slight leak but in your case maybe something else is going on, and you don't need to add anything and or the stop leak will just cause problems. Just Sayin'. Does sound like a leak though don't it?

http://www.youfixcars.com/automotive...ditioning.html


I'd want to "get smart" as I could on this beforehand if not taking it in. These days not too tough to get dangerous at least. Maybe even invest in some A/C tools, gauges and a vacuum. The pros don't add refrigerant to the low side when they do it, they run a hard vacuum on the system for at least an hour etc.

There's something about dessicant bags breaking and receiver dryers that sticks in my mind with that era too. Best to make a definitive diagnosis and then go from there before proceeding.

 

Actually, they do add to the low side but they often do it, if they really are pros, through the AC manifold gauge set so they can see the fluid going in via the view glass and keep track of the pressure.

The accumulator (dryer) must be replaced it I decide to evacuate the system. If there is moisture in the system it can do more damage later on. So breaking the closed loop of the AC system only opens up a can of worms and gets me knee high in money and time and a truck off the road.

Yes, I can rent the gauge set, yes I can rent the evac pump but unless it turns out it is the compressor*, which no leak stop product can fix, the $40 is worth the investment (money back if it fails to work) to get me on to bigger and better things while there is still some Summer left... if you know what I mean.

If you really want to learn something, check out the reviews and the youtube videos on the specific product I mentioned.

I will report back in a few days with how it turned out. Please... I am not the expert here and I'm sure I will soon feel the rath of those that are. I am only trying to get this fixed soon. My little doggie cannot stand the heat and I am rippin' mad I was sold a truck with a (knowlingly) bad AC system and not told about it, upfront.

*There is UV dye in this product so it will show where the leak(s) is prior to sealing it up. That gets me knowledge for the next time or if I want to go further and replace parts.

 

For sure let us know what you find. The A/C on my 09 works OK but wouldn't win any awards. Nothing to compare it to really, so I dunno.