do NOT mess with the A/C on 4th Gens

[T4RBoarder]

IMHO don't mess with the a/c ever on these trucks cause it can be a pain in the butt.

Story behind this is my brothers A/C crapped out and I bought two recharge cans with a gauge. I put 1.5 cans of refrigerant in the system and then decided to check my system to see if it needed any. In a nutshell the gauge with the kit was bad and I overcharged the system. I tried to bleed the system a little bit and ended up letting too much out. I then tried to put just enough in to get it to work and overcharged it just barely. It blew hot air and the compressor cycled and would only run for a couple seconds.

I took it to the shop and found out that this system is VERY picky to how much charge is in the system, just a little much or too little results in the same effect and the compressor cycling every couple seconds. Also, at least on my truck, the sticker for the A/C system had incorrect charge information..the correct information is in the service manual it took three trips to get the correct amount of charge in order to get the A/C to work. So unless you are really good I would not mess with it.

 

[EH007]

The A/C system in every vehicle is "picky" when it comes to proper charging. If you invest in a decent set of gauges instead of relying on the cheap ones sold with the recharge kits, you shouldn't have any worries. The good thing is that overcharging or undercharging the system usually just requires a slight adjustment and nothing more.

I definitelyw wouldn't advise putting in more than a can at a time (depending upon the size you purchase) without checking the pressures first. If the A/C system is low, it usually only takes a small amount of refrigerant to bring it back to normal. Go slowly next time and keep an eye on the pressures with a good gauge. You can also listen to the compressor clutch cycling on and off to get an idea of when the system is nearing a good charge.

 

[T4RBoarder]

I have two separate gauges and the one I used on mine was definitely cheap and def broken (didn't know), it was easier to use so I went with that one...it was showing low but then i hooked up the other gauge and it showed way high. Then I couldn't get the right setting. I've done two other cars with recharge kits and both went flawless but mine was torture.

 

[toto]

R134a is very picky if you're used to the old days of R12. You could be a mile off with the old stuff and the system usually worked fine. R134a has to be within just a couple of ounces or else it doesn't work.

At least the 4Runner still has a sight glass, which helps you get close.

 

[Bradky32]

AC

If you are low the sight glass will look foamy/have bubbles. Forget about your gauges. Charge it with R134a until the sight glass goes clear and STOP. If you do that, you cannot go wrong. The only other way is to evacuate the system, pull a vacuum on it, and use a refrigerant scale to charge the system with precisely the correct amount(in ounces).

 

[NCSCOTT]

Re: AC

If you are low the sight glass will look foamy/have bubbles. Forget about your gauges. Charge it with R134a until the sight glass goes clear and STOP. If you do that, you cannot go wrong. The only other way is to evacuate the system, pull a vacuum on it, and use a refrigerant scale to charge the system with precisely the correct amount(in ounces).

:iagree:

That is exactly correct. The ONLY way to put the correct amount of refrigerant in a system is the above method. Those Walmart kits can be troublesome.

 

[eskimochaos]

Re: Re: AC

:iagree:

That is exactly correct. The ONLY way to put the correct amount of refrigerant in a system is the above method. Those Walmart kits can be troublesome.

Can someone post a pic of where this window is located?

Does the V8 differ?

 

[NCSCOTT]

Re: Re: Re: AC

Can someone post a pic of where this window is located?

Does the V8 differ?

Not sure about the V-8 location. I would think they would be the same.

Open the hood. Look down in front of the radiator and to the left just to the right of the passenger side headlight there is a small squareish metal cube with a small dime size sightglass facing up on one of the A/C hardlines. With the A/C turned down to low take a look at the sight glass. There should be no bubbles or cloudyness. It may look like the radiant heat coming off the pavement on a hot summer day in the sight glass, but NO BUBBLES. BUBBLES=Bad. Under Charged or a blockage in the system.