2004 Rav4. A/C was cool but not cold last summer. A few weeks ago I got in my wife's car when it was 95°F outside and warm air came out the vents with A/C on. Wife said it takes time for the air to get cool. About 10 minutes of driving later, the air got a little cool. I added about 10oz of R134A and the air got cold. That lasted about 2 weeks and the air is back to warm. Bought some gauges. The readings were Low: 14psi High: 120psi. Added about 5oz of R123A and readings went to Low: 30psi High: 150psi. After a couple days, the air is warm again when it's 95°F outside but comes out cooler when the outside air is 80°F. I assume there's a leak. Just added some more R134A with UV dye but I don't see any dye lighting up after running it for 10 minutes. Will it take longer than that to get the dye to leak out?
A/C troubleshoot
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You will probably need a black light to see the dye. I'd check the schrader valves and see if they are leaking. At 300k if the compressor is original, I'd suspect it to be leaking.
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Look for any evidence of UV dye in the water that drips under the car from the evaporator. That's probably where the leak is if you're not seeing it anywhere else.
I just did the dye thing on my wifes car. She ran it for a day and I checked it with a UV flashlight at night. I was afraid the compressor main seal had failed, nope. There was some odd fluorescing on one of the hose crimp fittings. The fitting was wet with oil. I sprayed the fitting with soapy water and after a bit it was blowing bubbles. Ah, there's the leak. My brother and I will replace the hose and recharge the system this weekend (he has the vacuum pump and other gear).
Checking the condensate is a good tip for future reference, thanks, Powerglide.
Checking the condensate is a good tip for future reference, thanks, Powerglide.
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Originally Posted By: spasm3
You will probably need a black light to see the dye. I'd check the schrader valves and see if they are leaking. At 300k if the compressor is original, I'd suspect it to be leaking.
I have a black light and yellow glasses. The compressor is jammed under the alternator so it's hard to see it good.
You will probably need a black light to see the dye. I'd check the schrader valves and see if they are leaking. At 300k if the compressor is original, I'd suspect it to be leaking.
I have a black light and yellow glasses. The compressor is jammed under the alternator so it's hard to see it good.
Originally Posted By: irad
Remember to add a PAG oil charge before you add R-134a. This will prolong the life of the compressor and seals.
Especially if the compressor is mounted low! It will lose oil too!
Remember to add a PAG oil charge before you add R-134a. This will prolong the life of the compressor and seals.
Especially if the compressor is mounted low! It will lose oil too!
Denso compressors do not generally leak, I've seen some Chevy Duramax trucks with over 500,000 miles on the original Denso Compressor, Not saying it is impossible....Just unlikely.
It takes a little while for dye to find small leaks, Up too a couple days of running the system.
Service Ports need to be checked first. Losing Freon also emits refrigerant oil wherever it's leaking at, Look for oily spots on hoses, crimps, joints etc.
The TXV valve is mounted to the Evaporator in the Evaporator Case, That is 2 O-ring leak points you cannot see & probably not enough to show up at the evaporator drain with the small amount of dye you used. IIRC, The cold side of the TXV is wrapped with that Tar/Cork insulator [censored], And needs to be removed/cut to see if dye is present.
I have a "Blue Point" Dye Injection Kit, & inject at least 2 ounces of dye, I doubt "Freon with dye" has half that.
.......The censored words on this site are unbelievable....... I wasn't using foul language!
It takes a little while for dye to find small leaks, Up too a couple days of running the system.
Service Ports need to be checked first. Losing Freon also emits refrigerant oil wherever it's leaking at, Look for oily spots on hoses, crimps, joints etc.
The TXV valve is mounted to the Evaporator in the Evaporator Case, That is 2 O-ring leak points you cannot see & probably not enough to show up at the evaporator drain with the small amount of dye you used. IIRC, The cold side of the TXV is wrapped with that Tar/Cork insulator [censored], And needs to be removed/cut to see if dye is present.
I have a "Blue Point" Dye Injection Kit, & inject at least 2 ounces of dye, I doubt "Freon with dye" has half that.
.......The censored words on this site are unbelievable....... I wasn't using foul language!
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Originally Posted By: clinebarger
Denso compressors do not generally leak, I've seen some Chevy Duramax trucks with over 500,000 miles on the original Denso Compressor, Not saying it is impossible....Just unlikely.
It takes a little while for dye to find small leaks, Up too a couple days of running the system.
Service Ports need to be checked first. Losing Freon also emits refrigerant oil wherever it's leaking at, Look for oily spots on hoses, crimps, joints etc.
The TXV valve is mounted to the Evaporator in the Evaporator Case, That is 2 O-ring leak points you cannot see & probably not enough to show up at the evaporator drain with the small amount of dye you used. IIRC, The cold side of the TXV is wrapped with that Tar/Cork insulator [censored], And needs to be removed/cut to see if dye is present.
I have a "Blue Point" Dye Injection Kit, & inject at least 2 ounces of dye, I doubt "Freon with dye" has half that.
Thanks, this is helpful. The "freon with dye" was 10 oz of refrigerant plus 2 ounces of other stuff. Since I only added half a can, it's less than 2 oz of dye in the system.
Denso compressors do not generally leak, I've seen some Chevy Duramax trucks with over 500,000 miles on the original Denso Compressor, Not saying it is impossible....Just unlikely.
It takes a little while for dye to find small leaks, Up too a couple days of running the system.
Service Ports need to be checked first. Losing Freon also emits refrigerant oil wherever it's leaking at, Look for oily spots on hoses, crimps, joints etc.
The TXV valve is mounted to the Evaporator in the Evaporator Case, That is 2 O-ring leak points you cannot see & probably not enough to show up at the evaporator drain with the small amount of dye you used. IIRC, The cold side of the TXV is wrapped with that Tar/Cork insulator [censored], And needs to be removed/cut to see if dye is present.
I have a "Blue Point" Dye Injection Kit, & inject at least 2 ounces of dye, I doubt "Freon with dye" has half that.
Thanks, this is helpful. The "freon with dye" was 10 oz of refrigerant plus 2 ounces of other stuff. Since I only added half a can, it's less than 2 oz of dye in the system.
Alright, I don't buy that kind of freon so I didn't know, From your pressures your undercharged anyway....Add the other half of the can. Some claim you CANNOT charge by pressure, While there is some truth to that, Grasp the Low side line out of the evaporator, It will get real cold as you approach max charge, keep an eye on high side pressure....Idling in the shade at 95 degrees ambient with the condenser fan on should yield 220-250 psi.
On that rav4 check the high pressure hose for wetness and the corners of the condenser
Originally Posted By: clinebarger
Alright, I don't buy that kind of freon so I didn't know, From your pressures your undercharged anyway....Add the other half of the can. Some claim you CANNOT charge by pressure, While there is some truth to that, Grasp the Low side line out of the evaporator, It will get real cold as you approach max charge, keep an eye on high side pressure....Idling in the shade at 95 degrees ambient with the condenser fan on should yield 220-250 psi.
The pressure goes up to about 25 psi and then it stops. I keep adding the R134A but the pressure doesn't go any higher on the low side. Or very slowly. Is that normal or is it leaking out right away?
Alright, I don't buy that kind of freon so I didn't know, From your pressures your undercharged anyway....Add the other half of the can. Some claim you CANNOT charge by pressure, While there is some truth to that, Grasp the Low side line out of the evaporator, It will get real cold as you approach max charge, keep an eye on high side pressure....Idling in the shade at 95 degrees ambient with the condenser fan on should yield 220-250 psi.
The pressure goes up to about 25 psi and then it stops. I keep adding the R134A but the pressure doesn't go any higher on the low side. Or very slowly. Is that normal or is it leaking out right away?
That's the TXV Valve restricting flow of freon into the Evaporator because the Evaporator Temp is high. Once you get enough freon in the system for the Condenser to turn the refrigerant to pure liquid, The TXV will open up (Evaporator Temp Drop) & the low side pressure will start to increase
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JHZR2
Staff member
You are undercharged, and it's your duty to find and fix the leak before further charging.
You're in the right path. Also consider an electric sniffer.
Are you sure you didn't get air in when you charged some in?
Have you verified by static pressure reading that there really is liquid in the system?
You're in the right path. Also consider an electric sniffer.
Are you sure you didn't get air in when you charged some in?
Have you verified by static pressure reading that there really is liquid in the system?
Originally Posted By: Leo99
Thanks, this is helpful. The "freon with dye" was 10 oz of refrigerant plus 2 ounces of other stuff. Since I only added half a can, it's less than 2 oz of dye in the system.
When you added the "freon with dye", did you have the can upside-down? I almost missed that little detail when putting the "freon with dye" in my wife's car.
Thanks, this is helpful. The "freon with dye" was 10 oz of refrigerant plus 2 ounces of other stuff. Since I only added half a can, it's less than 2 oz of dye in the system.
When you added the "freon with dye", did you have the can upside-down? I almost missed that little detail when putting the "freon with dye" in my wife's car.
Are you sure that the compressor is turning on?
Originally Posted By: Rick in PA
Originally Posted By: Leo99
Thanks, this is helpful. The "freon with dye" was 10 oz of refrigerant plus 2 ounces of other stuff. Since I only added half a can, it's less than 2 oz of dye in the system.
When you added the "freon with dye", did you have the can upside-down? I almost missed that little detail when putting the "freon with dye" in my wife's car.
I turned the can about 90°. Not quite upside down.
Originally Posted By: Leo99
Thanks, this is helpful. The "freon with dye" was 10 oz of refrigerant plus 2 ounces of other stuff. Since I only added half a can, it's less than 2 oz of dye in the system.
When you added the "freon with dye", did you have the can upside-down? I almost missed that little detail when putting the "freon with dye" in my wife's car.
I turned the can about 90°. Not quite upside down.
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