Air Conditioner - Low Speed / Idle issue. (1 Viewer)

[04gx470]

I'm having some issues with my AC, hopefully someone can chime in and help out..

Background:
2004 GX470 ~230,000 miles.

Issue:
When the car is idling or I am in stop / go traffic - the AC blows warm air. When I am driving at normal speeds, say above 30mph, the AC blows cold air.

What I have diagnosed:
Condenser Fan Fuse - OK
Condenser Relay - OK
Magnetic Fan Relay - OK
The condenser fan turns on initially when I turn the car on and then turns right off.

 

[greenscobie86]

Mine is having the same issue, I recently did a bunch of front end work and had to put in a new A/C condenser though.

My suspicion is that I overfilled the system but won't have a solid answer on that until I'm able to hook my truck up to an A/C machine and evacuate/refill the charge to factory spec. My reading on the HVAC system for these trucks has pointed to the fact that these 120's are pretty sensitive to the charge of the system.

 

[04gx470]

Mine is having the same issue, I recently did a bunch of front end work and had to put in a new A/C condenser though.

My suspicion is that I overfilled the system but won't have a solid answer on that until I'm able to hook my truck up to an A/C machine and evacuate/refill the charge to factory spec. My reading on the HVAC system for these trucks has pointed to the fact that these 120's are pretty sensitive to the charge of the system.

When you turn on your car, and turn the AC on - does your condenser far turn on and stay on? Please let me know.

I looked through threads to see if anyone reported a broken fan/motor - didn’t see anything.

 

[greenscobie86]

Condenser fan does turn on and cycles after running for a little while initially.

 

[04gx470]

Condenser fan does turn on and cycles after running for a little while initially.

Mine turns on and then turns off right away.

 

[greenscobie86]

Sounds like a classic case of low refrigerant to me honestly.

 

[04gx470]

Sounds like a classic case of low refrigerant to me honestly.

Ok. I’ll stop by autozone and get a refill can. I guess at 230k, it’s fair game.

 

[SteveH]

You really should measure the pressures before simply adding refrigerant. Or, add only 1/2 a can at a time and see if that fixes the problem.

 

[greenscobie86]

You really should measure the pressures before simply adding refrigerant. Or, add only 1/2 a can at a time and see if that fixes the problem.

Words to live by. Exactly what happened to me when I blindly dumped in a bunch of refrigerant after rebuilding my truck.

 

[04gx470]

You really should measure the pressures before simply adding refrigerant. Or, add only 1/2 a can at a time and see if that fixes the problem.

Is it possible the fan is bad? I haven’t seen a single thread about replacement.

 

[04gx470]

I do plan to check it before filling. The bottle comes with a pressure gauge.

 

[bigredmachine]

you should check the pressures before adding but it is a safe bet that you are probably low on Freon. also just be aware that it is totally normal to have some less performance out of the ac system when at idle verses while driving due to less air flow over the condenser, that's why the fan gets installed

 

[04gx470]

you should check the pressures before adding but it is a safe bet that you are probably low on Freon. also just be aware that it is totally normal to have some less performance out of the ac system when at idle verses while driving due to less air flow over the condenser, that's why the fan gets installed

The plan is get a can of r134a. Plug in low side, check level, add if necessary.
I initially wanted to drop it off at a local shop, but after checking the fuse and both relays it comes down to either low Freon (possible leak given the age and mileage of my truck) or faulty fan motor, latter being unlikely as I have found zero threads on it.

 

[bigredmachine]

or faulty fan motor

the condenser fan will cycle on and off as the ac compressor cycles on and off so there is air flow over the condenser. taking it to the shop they will be able to add a uv dye to the system to aid in leak detection so that is not a bad option going that route

 

[04gx470]

the condenser fan will cycle on and off as the ac compressor cycles on and off so there is air flow over the condenser. taking it to the shop they will be able to add a uv dye to the system to aid in leak detection so that is not a bad option going that route

while I don’t disagree, the repair will likely outpace the KBB of my truck. If I can refill the AC and keep going — it’ll be ideal.

 

[GXO]

Once you get modding you won't care about KBB anymore. I am so far over anything I can get for mine I don't care anymore lol

 

[04gx470]

Once you get modding you won't care about KBB anymore. I am so far over anything I can get for mine I don't care anymore lol

haha. I hear you. This used to be my daily driver, now I use it as a back up car. Other than delete air suspension and 4Runner wheels -it’s stock.

I’ll report back after checking / filling the AC system.

 

[04gx470]

Update: I started the truck this morning. Same story, fan turned on and turned right off. Through the Freon view port, I saw a lot of bubbles going through, so I suspected it would be low. I then measured the level via the refill can and it was in fact very low. I ended up emptying the entire 18oz van and still couldn’t get to 50psi. The air is much cooler in the truck while idle and the fan is working. I’ll be picking up another can of r134a. If it doesn’t last very long, I’ll drop it off at a shop so they can find a leak.

 

[greenscobie86]

Thanks for the update! Hopefully the newly added freon stays in for another 230k miles!