Why is my air conditioner weak?

My cabin air conditioner isn't putting out like she used to. In all but the most oppressive weather, I used to be able to use fan setting 2, and the cab would be chilly. In fact, I'd often have to set the cabin thermostat a few detents above full chill or it would be too much.

This summer, I need to use fan setting 3 and set the cabin thermostat full left, and it still doesn't really get all that cold.

Today, I had the refrigerant level checked. A dye stick was used, and 8/10 of a pound was added. Didn't fix the problem.

What should I check next?

Bad cabin thermost, perhaps? Edit: probably not, as the A/C is weak even when the engine hasn't warmed up yet.

Evaporator coils clogged?

Thanks for any suggestions.

 

Wash the radiator/condenser really well. Mud/road grime gets trapped between the two

How was the level checked? Evac and recharge?

 

Not sure.

I don’t think a full evacuation was done.

Not sure exactly how the leak check was performed.

I was charged for a dye stick.

 

I've never heard of a dye stick, dye comes in a can with a small amount of refrigerant, in a bottle as pure dye with a carrier oil, or pre-mixed with refrigerant oil.

If the system wasn't evacuated and recharged there's no way to know how much refrigerant is in there, you can often get "close enough" with pressures but if there's an issue in the system like say a stuck expansion valve, failed fan clutch, dirty condenser, weak compressor, plugged condenser, etc pressures will be skewed.

8/10 of a pound or about 12 oz is over half of the total system capacity of about 20-21 oz so hopefully it's not overcharged now.

You can do some basic diagnostics without gauges but you really need gauges to see what pressures are running and check line & vent temps.

Something you can easily do to see if the refrigeration system is working is to run the truck with the A/C on high and check to see if the suction line is cold, if it is then you may have a blend door issue but if it's barely cool or not cool at all you have an issue on the refrigeration side and will need to do further diagnosis.

Also as @Bishop84 said check to make sure your radiator and condenser aren't full of trash.

 

https://www.youtube.com/watch?v=EKERvNk9iWs
The Car Care Nut, a Toyota Master Diagnostic Technician, opened his own shop after a long dealership career, and continues to maintain his certifications, training, and database subscriptions. He's produced (and continues to produce) videos that explain Toyota systems for DIY-ers to help in understanding how vehicles work.
This RAV4 has a mysterious AC problem. TCCN investigates...

 

Replace the blower filter?

 

Reading conflicting info. Does evac and recharge remove oil as well or just refrigerant?

 

2nd this, check the drain isn't blocked too

 

Yeah, check cabin filter would be my first move. Might get lucky.

 

Any luck I’m having the same issue with my A/C

 

The blower and the cabin filter are only 2 months old. It's not an airflow issue.

 

- you have to have the correct amount of refrigerant in the system. Too much or too little and performance will drop. A service machine is really the only way to truly make sure you have the correct amount

- you have to have good heat exchange happening at the condenser. If its covered with bugs and shit that's a problem. Run the a/c in the driveway and spray the condenser with a hose. If the cooling improves then it may need a condenser

- just because the fan blower is brand new doesn't mean its spinning fast enough to blow cold air out the vents properly. It could have a poor connection at the blower connector or fan speed resistor that will limit the available voltage to make the fan motor spin. Does it sound like the fan is spinning fast? Maybe sit in someone else's truck and compare?

 

A system evac establishes a complete vacuum if there are no current leaks. An evac removes everything: refrigerant, oil and moisture. It will quickly confirm a system leak if/when it can't hold that vacuum.

 

When I first got my 2013 2.7 base in 2020, I got a new cabin filter - the kinds that does allergens, etc. Also had to clean out a whole lot of fluff and acorns. It still kind of sucked when it blew (sorry).

I checked everything and it was fine, but I also read a lot of posts on various forums that Tacos are kind of known to have a sucky AC system.

That being said, I figured I would try two things to help it along.

1. Tint the windows with "ceramic" tint - although it is illegal to tint front side windows in NH, "clear" ceramic tint is available that, although clear, blocks an amazing about of IR heat (considering it's clear). I put the darkest available for the rear. Being a Base, that's all I've got.

2. Getting rid of the restrictive cab filter and replacing with (in my case) a K&N. I'm not concerned with allergens, etc., I just wanted the least restrictive filter - not sure how others compare.

Doing above made a pretty big difference in the AC's ability to cool the cabin. For example, one of the first things I noticed was that when set to NOT circulate, I could feel air being forced through the vents from driving forward, which I didn't feel with the more restrictive filter. Like you, I needed to use at least "3" on the speed dial, but now (after initial cooling) am fine with 1 or 2 (depending on cloud cover, etc.).

 

Made mine better by doing the following.

-charged it myself with professional machine
-replaced compressor radiator and condenser
-replaced blower motor and resistor
-replaced inline filter if there was one
-replaced fan clutch

there’s a bulletin to add secondary fan.

anything else is probably more work. Line lines (which may be unnecessary) and evaporator IF that requires dash remove.

I do have an annoying clicking I need to figure out. That could be debris or a vent adjuster whatever it’s called gone bad.

 

Do you notice the weak a/c only when stopped or also when moving?