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RIP 3/13/23
May 20, 2020
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2002 Honda CRV, AC is very cold when driving but when stopped at a light it's not cold,. Soon as you drive and the rpm goes up to at least 2000, it's cold again...I put a can of 134 in the system, no difference. It was the same last summer so it's not leaking bad if at all...what do you think the problem is ? It's an old heap so no intentions of putting money into it..just curious, thanks
You cant just "add" a can of Freon, every vehicle takes a specific amount - too much/to little can cause issues.

This model uses R134 refrigerant in the A/C system.
Reported capacities are for estimating purposes only.
ALWAYS refer to manufactures service manual for
recommended repair procedures and system capacity.
R134 02-06 1.1-1.27 LBS
With any operation requiring a refrigerant line disconnect
add AC service, i.e. evacuate, recharge and test for leaks.
Add for refrigerant cost.

specs per CCC1
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Still blowing the same amount of air, just not cold at idle? If so I would say its a possibility the compressor is going out. At RPM is working enough to build pressure in the refrigerant, but with the lower RPMs its not. If you are not achieving the correct pressures on the high pressure side of the system it wont cool properly when going through the expansion valve and condenser.
I just went through this with my daily driver. It might be overfilled. Get a pressure gauge and follow the process to set it to the correct pressure/weight of refrigerant.
When stopped, the fan should draw air through the condenser. Either the fan isn't working, or the high pressure switch on the ac line isn't telling it to turn on.
Yes, still blowing the same amount of air at idle..if I stop the ac instanty warms even if for 15 seconds... Fans, when the ac is switchen on the the aux fan come on or both? Water temp gauge is showing normal. It could be overcharged but like I said it was the same before adding the 134......
Sit in park and rev the engine to 2k. If it still gets colder, then it wont be the fan or clogged condenser. If it stays warm until you move (forcing air through the fins) that's a good place to start.
Random thoughts....

Could it be vacuum related? Is the AC blend door vacuum actuated?
Condenser is clean. AC on ,both fans running....When idling in neutral, 5 speed , bring the rpm up to 1500 gets the air cool again quite quickly. The climate control might be vacuum, the engine idles very nice so if it's a vacuum leak it's not obvious ...Maybe I should treat this like a sore dick and not fuck with it?
Sounds low on Freon to me. Take it to a shop with a good A/C machine, have them recover what's in there and measure it, evacuate it for at >LEAST< thirty minutes, then charge it with the right ammount of Freon using a SCALE to weigh it. Only way it'll be right, and R134a cars are very sensitive to over or under charging. Sometimes as little as an ounce or two either way will keep them from working at peak efficiancy.

This is >not< something that can be done at home by Joe Average, I don't care >WHAT< the parts store idiots say... :mad3:
I know this is chit chat, but put some fucking gauges on it at idle

you can borrow them from vatozone and do it in the parking lot
Hmmmm.... I'm still leaning vacuum related. A quick Google search indicates a vacuum check valve for your car.

Only reason I bring this up; is because when I stomp on the gas in XJ on a long steady hill climb, my AC cuts out because the vacuum controlled blend door closes and I lose AC. Once I clear the hill and resume normal cruising the AC comes back to normal.

Yours sounds like a reverse situation....
id throw some gauges on it after it sat a little bit and look at static pressures. You should see within a few psi of ambient IE static pressure is 75 psi and the temp outside is at 80*

Look up a r134a pressure tempature chart for it to be specific.

But i have looked up your car and did you know you can pull DTC codes out of the hvac control?

Heres a screen capture of the capacities. ill dig into it and see if there is anything else. But postal can also be right i have also seen that, but you would need gauges to verify.

2002 honda crv refrig cap.jpg
There is no VAC system on this unit after i dug further. You system uses motors. Im still leaning on low on refrig.

Did anybody ask if your compressor was actually running? Cycling possibly? anywhere heres the dtc test, cancelling is cut off but it just says cycle ignition

There is a cable controlled heater valve in the system but i doubt its your issue.

02 crv hvac DTC1.jpg

02 crv dtc pg 1.png

02 crv hvac dtc2.jpg
Well thanks for the dtc info...

The compressor runs steady when it's cold, got to check to see if it drops out at idle...
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I got a set of gauges and hoses at a garage sale for short money.....15 psi on the low side, 120 on the high, 75 degrees temperature outside.....I guess it needs a charge...
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