I would like to get the ac going in my truck, has anyone figured it out yet? 91 4runner 97 taco 3.4

 

vital has apparently but I have looked at the EWD's like crazy and i dont see how it goes together yet.

 

I'm in exactly the same boat. My 91 didn't come with it, but I've gotten most of the parts rounded up but not installed yet, except for the evaporator. I have a 97 Taco motor that came with the A/C compressor. I still need the hoses from the compressor and I need to figure out how to hook up the amplifier. Oh, plus install the condenser, fan, and whatever else goes along with it.

But I have to wait until spring. No need for it here right now.

 

So if you don't wire up the 5vze A/C amplifier, the A/C doesn't work at all? Even if you use all the 3VZE A/C components, it won't work right?

 

i have read threads on guys using both and it works. that is only adding to my confusion.

the good thing is that Vital is a member her and he used the 3.4 amp and apparently his works.

 

I don't know crap about wiring, but the guy wiring mine up said getting everything to work correctly wouldn't be a problem. 97 3.4L to 90 3.0 2 door

Next time I see him I'll ask him what the big deal is in getting the AC to work.

 

 

Hey Wabbit

I think that there are a few guys here that wouldnt mind kickin your wiring guy a few bucks if he could draw up a diagram on what is needed and how to connect it all. I would contribute cause its damn hot here in the summer.

 

X2

 

I am subscribing to this thread. I have neared the end of my swap and this is one of my questions as I begin to button everything back up and I don't want to make extra work for myself. I have all the stock once fully functional 1994 3.0 A/C components attached to my 1999 3.4 motor (I have the 3.4 compressor if it needs to be changed, I will have to locate a 3.4 A/C amp though). Want to know how to make sure they functions once my swap in finished. It gets hot and humid in Oklahoma.

 

i'm going to be looking into this very soon, just got my 3.4 swapped, and fired up a couple days ago. I just barely skimmed the ac drawings, but didnt start the wiring for them yet.

 

a member her????? haha it worked last i checked in summer. I'm running 3.4 amp, 3.4 compressor. everything else is from the 3.0. Vacumed and charged the system and it works. Also running the r134. Oh and dont forget to add some oil to the system.

 

LOL....my typing skills are sometimes lacking.

I think that most of us, well me at least, are stuck on the wiring aspect. I have gone over the EWD and still dont get it. I also am still unsure of what this is. Is this the high/low cutoff switch that I see in the EWD?

 

I got the a/c working by pissing off the 3L amplifier altogether. The thermister in the 3L was causing the problem so we removed it and put in an aftermarket adjustable temp probe and wired it up. Turned out good, you can set the temp down really low too. Now it gets down to 2 or 3 degrees (celsius) before it cycles, instead of 6 or 7.
Ive not had any problems at idle either. Im thinking that the idle control valve (or ECU)compensates anyway.
We wired the 3L amp up at first but the a/c wouldnt kick in until we bridged out the thermister wires.
Hope this helps someone.

 

Use the 3.4 ac amplifier.

 

This is total gibberish to me!

I dont even know what a thermistor is...hell i didnt even know that was a real word!

Wabbit, any word if your guy is interested in drawing something up?

 

OK, Im no expert but Ill try and explain a bit better.
Found this from a quick google "An a/c compressor is essentially a dumb device. It pumps when it is told to and is either on or off. The a/c control circuit is responsible for telling the compressor when to turn on and off. In the Toyota, this is done by the a/c amplifier, a circuit that monitors certain sensors in the system and decides how to control the compressor.
One function of the a/c amplifier is to monitor engine rpm and turn off the compressor as engine idle drops below about 600-700 rpm to prevent the engine from stalling. The speed at which this unit cuts out is often adjustable at the a/c amplifier under the dash. When a new engine is installed, it is necessary to retain the tach input to the a/c amplifier to allow it to turn on the compressor. However, with a V6 or V8 the engine rpm will be 1.5 to 2 times higher for a given rpm and the compressor will probably never turn off due to low idle speed."
The purpose of the thermistor is to cycle the compressor clutch at low temperatures to prevent freezing of the
evaporator.
So basically, the thermistor is a temp sensor/probe that is poked into the evaporator core. It tells the amplifier the temp and then the amp cuts the compressor at the set temp to avoid freezing of the evap core.
I got a manual thermostat ( small box with adjusting dial and probe/wire sticking out of it)for under $50, mounted it next to the amp and took the bottom off the evap box, and inserted the probe into the evap core next to the thermistor probe.(no need to remove the thermistor probe unless u want to). Unplug the 3L amplifier (I left it sitting in its place too) and splice the 2 wires from the new probe to the thermistor wires. Then u can set the temp to what u want ( Put a thermometer or temp sensor in the center vent, crank up the a/c and wait for it to cycle( compressor to kick out) and check what temp it gets down to, then adjust till u get it cool enough.

A quick way to test if this will work is - If u have the a/c all gassed up, hooked up and ready to go but it wont start ( ac light on dash wont light up) then unplug the ac amplifier and bridge out the two wires that go to the thermistor. The ac should work, if it doesnt then u have a problem somewhere else. just dont leave it bridged for too long or it may freeze up.
I have a 3.4 amp but didnt use it because the two systems are different so this was the easiest and quickest way to get it going. Took about half an hour.

 

you have a link to the adjustable thermostat?

 

I cant remember the brand I used but its supposed to be pretty good. Just ask a autoelectrician and they should have put a manual thermostat in at some stage.
Or do a search, not sure of the sites to go to but in the USA you should have some decent online auto stores. Just search for "car air-conditioner thermostat" and you should be right.
just a few to get u started
http://www.alibaba.com/showroom/car-...-showroom.html
http://www.alibaba.com/showroom/car-...-showroom.html

 

Mine worked from the start with the 3.0 amp.But the low pressure cut off has been fried and bridged for years!It will freeze your arse off!
Bigblock