95 Ranger A/C problem
Thread Starter
|
New User
Joined: Aug 2004
Posts: 8
Likes: 0
95 Ranger A/C problem
On my 95 Ranger w/ the 4banger the A/C is acting up. Tried to use it for the first time this summer and nothing but hot air.
The compressor engages only for about 10 seconds after you first start the truck.
Checked the r-134a, a little low and put a can in it. The pressure seems about right, around 45. I had to repeatedly start and stop the truck to put the can in.
Still does the same thing. AC cycles on, starts to get cold them blasts hot air. I have tried leaving the AC on while driving around town, but always hot.
Switched the relays around in the fuse box thinking the AC one might be bad, but I still have the problem.
Have you guys got any ideas on what to try next. These AC problems confuse the heck out of me.
-Nate
The compressor engages only for about 10 seconds after you first start the truck.
Checked the r-134a, a little low and put a can in it. The pressure seems about right, around 45. I had to repeatedly start and stop the truck to put the can in.
Still does the same thing. AC cycles on, starts to get cold them blasts hot air. I have tried leaving the AC on while driving around town, but always hot.
Switched the relays around in the fuse box thinking the AC one might be bad, but I still have the problem.
Have you guys got any ideas on what to try next. These AC problems confuse the heck out of me.
-Nate
Post Fiend
Joined: Feb 2003
Posts: 6,940
Likes: 2
From: Eastern WA
It sounds like a charge issue. Usually freon is introduced slowly and one watches the gauge to attain the proper charge. By doing this, you can get the correct charge without overcharging. Overcharging will also result in a high reading on the suction side. Maybe you need more freon still?
Senior User
Joined: Sep 2004
Posts: 235
Likes: 0
From: Indiana
It might just be your pressure gauge. Is is cycling on and off, or is just turning on for 10 seconds then stopping. If there isnt enough R-134a then the compressor wont stay on. The pressure will get to a certain level then the compressor will kick on and the press. will drop. It just sounds like there isnt enough R-134a. Also make sure to have the A/C on max, and the fan on high.
Posting Guru
Joined: Jun 2004
Posts: 1,635
Likes: 0
From: Niceville, FL.
You need to do the charging with engine running about 1200-1500 rpm. Put an electric fan in front of the grill to keep ambient air flowing to condenser and radiator. Normal airflow is disrupted with hood up. You can speed up the charging process by putting the refrigerant can in a pan of warm water (no more than 120 deg. F.). Keep in mind, if you're low on refrigerant THERE IS A LEAK somewhere. Sooner or later a real fix will be required. Buy an A/C thermometer at Auto Zone (about $5 or $6) to measure air temperature at center outlet. With vehicle in shade, hood down, Max Cool, windows up, doors closed and engine @ 1200 rpm; temperature at center outlet should shortly get to Blue Zone on thermometer when adequately charged.
Thread Starter
|
New User
Joined: Aug 2004
Posts: 8
Likes: 0
I have since put another can of freon in and the same thing still happens. The AC will run for 10 seconds and just turn off.
To clarify, the only time that the AC will kick on is right after the truck is started. I have the fan on high and the switch on max AC. It will kick on then for only about 8-10 seconds. It will not come on again after that.
If I start the truck and then wait a sec and then turn the AC on, nothing at all will happen. Just hot air out of the vents.
I can get the AC ice cold by turning the truck off and on to keep cycling the freon so I'm doubting the charge issue.
After the new can the charge is around 45-50 still. I'll look around for leaks though. Might have to take it somewhere to check the charge on both sides.
To clarify, the only time that the AC will kick on is right after the truck is started. I have the fan on high and the switch on max AC. It will kick on then for only about 8-10 seconds. It will not come on again after that.
If I start the truck and then wait a sec and then turn the AC on, nothing at all will happen. Just hot air out of the vents.
I can get the AC ice cold by turning the truck off and on to keep cycling the freon so I'm doubting the charge issue.
After the new can the charge is around 45-50 still. I'll look around for leaks though. Might have to take it somewhere to check the charge on both sides.
Posting Guru
Joined: Jun 2004
Posts: 1,635
Likes: 0
From: Niceville, FL.
It's possible you are overcharged or have a bad high pressure cutoff switch (located on the high pressure line between the compressor output port and the high pressure gauge port). First, measure the low pressure after the truck has sat and cooled overnight (before you start it); I think it should be ~ 100 psi (I'll try to measure mine tommorrow). Then start and run until it quits cooling, then remove the HPCO switch connector and measure the resistance between the pins of the switch. If no resistance (open) the switch has opened due to high pressure or is defective.
Post Fiend
Joined: Feb 2003
Posts: 6,940
Likes: 2
From: Eastern WA
Since it seems nobody has a clue where the charge is at, you need to get a guage set (suction/head side) and hook it up. Disable/jump the low pressure cutout and see where your readings are with the system at steady state. Post your pressures here, along with the ambient temp. Run the motor at about 1200-1500 rpm. The A/C systems of the last 30 or so years use a "critical charge"; there is no receiver to store excess liquid freon. With this in mind, you need to charge within a few ounces of the correct amount. This can be done by watching the pressures as you charge. BTW, when you charge you do NOT dump in the whole can, but rather charge based on operating pressures. Adding more freon just because it's available is not the way to go and will lead to frustration (in all odds, overcharge). BTW, when you are taking readings never allow the head side to get to 300 PSI; I do doubt this will happen to you but be aware of it. Also, never let the suction side drop to zero; this may draw air into the system. Just a heads up on the boundaries.
Last edited by CowboyBilly9Mile; Jun 17, 2005 at 12:43 AM.
Trending Topics
Posting Guru
Joined: Jun 2004
Posts: 1,635
Likes: 0
From: Niceville, FL.
After sitting overnight the R134A static pressure in my fully charged '99 Ranger A/C is 90 psi @ 90 Deg. F. ambient temperature (measured at low pressure port). If your static pressure is very much higher then you likely have overcharged. On my previous post I should have said infinite resistance instead of "no resistance". Sorry!
Last edited by Piffery1; Jun 17, 2005 at 12:49 PM. Reason: correct error
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Thread
Thread Starter
Forum
Replies
Last Post
waits3
1983 - 2012 Ranger & B-Series
4
Sep 15, 2012 12:48 AM
PowerstrokeDude
1994.5 - 1997 7.3L Power Stroke Diesel
9
Sep 21, 2006 10:28 PM
