r6dallastx

I have a 1990 v6 4x4 4runner 181000 miles. I found this web site a few months ago and I have found a lot of use information. I have never posted anything before because I have found all of the information that I need to know by doing a search on older posts. I did a search on a/c problem and I really didn't find anything that would help me. My problem is that my a/c, retrofitted from r12 to 134a, blows cold but not cold enough for Texas. It cools fine until 88° then it's just not enough. I took the temp at the vents with the a/c on it was about 44°-48°. I thought that it didn't have enough 134a so I when down to the Wal-Marts and bought one can, I put half of the can in and it seem to be blowing hotter. So I thought that I had too much so I when back to the Wal-Marts and bought a gauge that reads in psi. The gauge reads 33 psi with the rpms at around 800 and 25 psi at around 2000 rpm. I found a manual online for down load and it said to check the dryer if the glass had any bubble or if the lines hand frost or dew. The glass had no bubbles I only saw white on the glass and the lines had no frost or dew. The compressor doesn't not cycle on and off it's on all of the time. I'm thinking that I will just replace the dryer and have the system vacuumed down and add new oil and 134a. I have a set of real gauges but they are for r12 system. When I am driving it does blow a bit colder than when I just sitting traffic. I have washed out the condenser with my garden house it had no effect and the condenser fan turns on. I’m not sure what to do next. Does any one have any experience with Toyota a/c systems??

nunsa

Greetings cowboy,
Only kidding,
A couple of questions before I start: When you retrofitted did you vac the system down?
When you look at the sight glass it should be clear like looking at a glass of water, if there's bubbles it's usually low, now then, when I worked for Toyota in Arizona I did a lot of AC work and the customers always requested me because I could make there AC VERY VERY COLD! How you ask, one thing to check is the heater control valve it sits smack in the middle under the hood at your firewall, make sure that you heater control is set to cold and go look at the heater control valve, you usually can get more adjustment out of it towards the cold side, you have to remove the clip and slide the cable, I could get the ac blowing at 34 degrees, no sh**! Make sure that your going the right way! Your compressor should cycle on/off, another thing to check is the AC idle up, if it's not adjusted correctly your ac will shut off at idle, it's on the passenger side by the wheel well, it's a big white plastic screw, make sure that your idle is correct at idle w/the ac on, if not you might need to bump up the idle with this screw! Other things to check is your cooling system, I noticed you have a 3.0, make sure the coolant is full and the t-stat is good, the clutch fan also. and that dreaded HG isn't leaking! AC are touch, don't overfill them and don't under fill them! I can't remember, but I think at idle with the ac on it should be at close to 1000 rpm''s! The compressor should kick on at idle, if it's idling, give it a little gas and see if it kicks on, if it does, it's the idle up. I hope this helps you! Let me know! 10-4?
Harry

r6dallastx

I adjusted the idle, and the heater control valve, but it only came out a 1/6 of an inch. I did feel a bit cooler so it did help maybe 2° cooler. The coolant and thermostat are good cause the truck never over heats not even if it's 101° outside. The slight of glass is not clear it looks like it has milk in it. I bought the truck with the retrofit, so I don't know any of the history. I can hear the compressor turn on and I can feel the cool air cause its 93° right now and getting hotter, but I never hear the compressor turn off.

4-RUNNIN' FREAK

My A/C isn't that great either. It's been in the 90's here the last week, and it just sucks and always has in hotter weather. It can be that it's a larger area to cool with the same system my freind has in his Taco trying to cool off a 4Runner.

Once I run on the highway for awhile, it gets nice, but not as cold as other cars I have owned or rode in. I usually drive in 2nd (or with o/d off in 3rd) gear around town and burn more gas to keep me cool.
My truck doesn't drip a lot of water when the A/C in on compared to my friends Taco.

I'm gonna be looking at this thread and see what comes up.
I seem to have many issues with my truck.
I like cooooooold air. I love the winter because of the temps, but love the summer cause all the hotties.

Fink

I'll tell you guys straight up that I don't know anything about A/C systems but all of the 2nd gens I have been in have had VERY COLD air coming out of them...mine included. You may want to find you a local nunsa, sounds like he really knows what hes talkin about, or talk to him some more one-on-one to get a better idea of what to do.

Good luck and try and stay cool!!

Fink

Ironmike4x4

The amount of water does not mean anything, it's just the condensation from the humidity. Speaking of that, I had a customer come in today just because their A/C was "leaking" water. Came to find out they were from Arizona and were not used to the humidy effects on the A/C systems. My service manager had to explain to them it was normal operation.

4Runnin' have you maybe tried to blow out or hose off the condensor? Sometimes that will affect A/C performance.

4-RUNNIN' FREAK

Everytime I wash my truck I try to hit it.

As far as condensation, I had to poke around last year and it started to drip freely again. Water came out from wherever I stuck my finger where is leaks from on the passenger side. It's a metal tube that drips right onto the chassis.
It felt slimy, kinda like some home A/C's I powerwashed out.

I think I just like it colder than my truck can provide. It just was never great to me, even when new.

Ironmike4x4

You may want to take it to a professional MVAC mechanic and see if they can "tweak" your A/C system. I fooled around on mine and got it down to about 29 deg. F, but ran into the problem of iced water blowing through the vents so I had to back off a bit.

Ganoid

Typical r134 systems do have a larger cooling unit due to r134 being slightly less effecient. I have also read about differences in expansion valves where the r134 needs a smaller valve to run a higher pressure. I am fairly happy with my AC but if I lived in texas I think mine also would be less then adequate. You may want to try one of the hybrid refrigerants available.

Steveh29

Milky view in the sight glass is indicitave of a low charge on r134 - at least that's been my experience. Worst case scenario you could totally purge the system, flush and refill with the proper level of oil and refrigerant. My 2nd Gen came from the factory with 134 and it will definitely freeze you out of the vehicle. Even on the hottest days when I lived in Houston. Works great here in Southern California too.

r6dallastx

I think that I will purge and fill everything with new 134a and oil. For all know it may have air or something in the system. Do I have to buy a new dryer or I just vacuum out the system and refill with 134a and oil. Can someone let know the steps to purge and refill. Also does anyone know if I replace the dryer will that make it cooler, do they go bad??

Ironmike4x4

The dryer should be fine, the mineral oil usually just gets stuck in there but wont really affect performance much.

Steveh29

My experience is you can reuse the drier in some cases. If your system isn't contaminated with water you might get away with pulling the drier and plugging it to prevent it from absorbing a ton of moisture from the atmosphere while you work on the system. If you live in an low humidity area, even better.

r6dallastx

I just came back from give my friend a ride and after adjusting the idle and the heater control valve it did feel colder i even turned down the fan speed. It's later in the afternoon now and it's only around 87°. I will try to clean the metal tube that drips water. Thanks for the tip if you have any more let me know and i'll try them out

nunsa

That sight glass should be clear!!! Evap/drier! Before you replace the expensive parts I'd drain the system, vac. it all down and recharge it, if the sight glass is still milky, yeah - evap/drier!

r6dallastx

I have just finished doing some maintenance on my a/c system. I cleaned my condenser at the car wash with engine degreaser. I adjusted the heater valve. I cleaned out the blower fan inside the cabin with some water and compressed air. I bought a vacuum pump form ebay and I vacuumed my system out. I vacuumed the system out for about 3 mins. No oil came out it had about -7 psi and it held. I added one can of 134a (12oz) and about another (3oz) from another can until I had about 26 psi at 2000 rpm at the low side. The manual calls for 21 psi - 28 psi. I don’t have a high side gauge just a low side gauge I bought it at walmart. At first it didn’t feel any colder than before, but I drove her for one day and I took the temp at the vents, it was 91°-89° outside and I was sitting in my drive way, the temp at the vents was 19.5°-26° . I had the fan on low and on recirculation. Before I did all of this it was around 39°-45° at the vents. The only think that I can not figure out is that the compressor doesn’t cycle on and off it’s on all of the time. Other than that I’m very happy with results that I have. if anyone else has any more ideas on how to get my a/c colder let me know. I have a crazy dream of getting the temp down to 10°

CynicX

did you clean the evaporator?

r6dallastx

No, i didn't touch the evaporator

Ironmike4x4

30-45 is very good, but I'm seriously concerned with the 19-26. You can freeze your condensor that way.

dragon564

Okay in Atsugi Japan it is 102F today. Two weeks ago I had the A/C serviced, I needed some R12 added to the system, I saw the bubbles in the sight glass. I know the tech and he knows me. He told me that I needed to clean both the condensor...the on inside the cab and the one up front. I did the inner first taking out the G box and fan unit to get to it. I fan was just about clogged and I am surprised I felt air being moved through the system at all. The A/C condensor was in no better shape, Lots of brakes parts cleaner and low pressure air. After that I could really feel the air blowing in my face and the truck smells soooo much better. It was not much colder. On Sunday I took off the front bumper and grill and cleaned the unti in the fron and the aux fan that is up there also. More brake parts cleaner and some engine de greaser. From all the muddin the truck has seen it was pretty dirty up fron also, I noticed right after that the engine also run cooler. We just went out to lunch and in five minutes I was turning the A/C down, my pax were saying it was too cold....So I would say clean the whole system up and it should help alot....I was suprised at the amount of dirt that had built up and collected on all the parts.......