Aircon Idle Up for 1UZ 4Runner

[twisty_toy94]

I just finished getting aircon put back into my 4runner after having the Lexus V8 fitted for over 2 years......The aircon works great once driving, but doesn't work at idle. I assume this is becuase I have no idle up hooked up. If I manually lift the revs to about 1200rpm the aircon kicks in.

Does anyone know of a simple way to wire up a Aircon Idle Up? I'm running a Crown ECU with a Venom Loom. Is it just a matter of hooking up the wire that engages the clutch on the AC pump to a wire on the back of the ecu?

Any info would be great.....thanks.

 

[hi-lex]

mine hasnt needed it,comp kicks in evan at 750rpm , but it should just be an input to the ecu

 

[hi-lex]

mine hasnt needed it,comp kicks in evan at 750rpm , but it should just be an input to the ecu

 

[twisty_toy94]

hmmm.....wonder what makes yours different to run at the lower revs??

We've tried different gas pressures, with no results.

The other confusing thing is all the wiring for the AC is currently completley independent of the Lexus wiring (still the stock 4runner wiring). How does the aircon know the revs have been lifted and to cut back in?

 

[Lextreme II]

Make sure your ac compressor is good. Lots of time bad compressor will have heavier load and kill the engine during idle.

 

[1uzvl]

Dunno bout hiluxs but the 2h deisel landcruisers require rpm before the comp will cut in,because the get me all the time regassing them.Its like put gas in, fire it up,comp wont cut in,what?Must be a electrical prob,so you check fuses and so on. Was it like this before the conversion?

 

[bansheebuzz]

some toyotas have a control unit behind the glove box that controls the ac. There is a tacho referance to this unit. it will require x amount of rpm or it wont cut in. It should be adjustable

 

[twisty_toy94]

Make sure your ac compressor is good. Lots of time bad compressor will have heavier load and kill the engine during idle.

Compressor is fine and has been checked.....my first compressor leaked badly, so have had it replaced.

Dunno bout hiluxs but the 2h deisel landcruisers require rpm before the comp will cut in,because the get me all the time regassing them.Its like put gas in, fire it up,comp wont cut in,what?Must be a electrical prob,so you check fuses and so on. Was it like this before the conversion?

The aircon used to work fine at idle with the old V6, but the engine would idle up to just over 1000rpm when the aircon was switched on. All fuses have been checked and are fine. When the car is first started and it idles high to warm up, the aircon works fine....but as soon as the motor heats up and drops the idle, it cuts out.

some toyotas have a control unit behind the glove box that controls the ac. There is a tacho referance to this unit. it will require x amount of rpm or it wont cut in. It should be adjustable

Sounds like this could be the problem...and if it runs off the wire to the taco, then it would be hooked up. I might disconnect the wire running to my taco and see if that makes a difference.

 

[sideshow]

the 1uz has a 4cyl tacho signal
so the rpm will be less than what the orig 6cyl engine used to send to the a/c amplifier

as said above see if there is an adjusting knob
my hilux has a knob and turn it one way see what rpm it turns on at

or you could by a signal multiplier and multiply just the tacho signal just goin to the a/c amplifier this would make a/c cycle in and out all the time

mine turns of below 800 or 900 rpm so when at lights i shift into nuetrasl for a split second this turns a/c on for abit again

 

[bea_vis]

Im interested in this thread, ive just hooked up my ac, it works fine at idle though. However i would like my rpm to bump up as per factory so as my alternator can still produce a decent current when idling about.
When my comes on my rpm drops a little which is mainly noticable in my alternator output.
Does anyone know whether the ACMG (pin 8 on the 22pin crown ecu) should be connected to the ac clutch to increase idle speed?
Also what about the A/C control assemble (pin 10 on the 22pin) is that an output or an input to the ecu?

Anyhelp is appreciated guys

 

[samsdad]

What is your UZ in?

What is your UZ out of?

You can have it wired correctly but incorrect refigerant will cause problems

 

[bea_vis]

Hi, thanks for the reply Samsdad. It's a uzs131 crown motor in a ln106 hilux, with the manual 5speed. Didn't know about the refrigant problems will quiery the AC man next time I see him.

It works fine cooling wise, just stalls when coming down from revs over 3000 when you put the clutch in. Like a sudden stop or something.

Is it a case of having all the AC going through the ecu and not being able to just have the ecu getting a signal from the AC to boost the revs?

Any help is greatly appreciated.

 

[sideshow]

ecu just needs ac signal
don't use acmg
if u still have issues it's in your ac amplifier and
u have to fiddle with it or trick it
I got my 92 hilux to work ok
I can help if u bring car to me in exchange for some
folding stuff hehehe

 

[sideshow]

hey bea you might have other issues if it stalls from
3000 rpm or does it do it only with air on

 

[bea_vis]

Na sorry I mean if your driving n have to stop suddenly like at a roundabout, you put the clutch in and the revs drop too low for the motor and it stalls itself.
The AC isn't going through the ECU currently, think I need to wire it through for it to compensate idle speed.
The mechanic I had gas it and wire it was pretty knowledgeable but did have problems setting up the amplifier, tried two that were adjustable via a trim pot but finished up using a non adjustable one.
I would drop it by and have you sort it but it's a 6hour drive to bris Vegas from here, cheers

 

[sideshow]

does it only stall when the air is on
what happens when the air is off
does the air compressor work at idle
there is also rpm differences between 1uz n 4runner
so could be that but doubt it
tell yr auto elect to look outside the square heheheh
find the a/c fire and run it to a/c compressor wire so it gets 12vs when compressor is on
if that doesnt help then its not to do with air con and could be heaps of other sheit
which is a matter of trial and error thinking what it might be

u said it runs gas?
does it do it only on gas or petrol aswell
could be heaps of stuff

 

[bea_vis]

Yep only stalled when ac on. Was because idle was too low with compressor load. AC still worked at idle, but alternator output dropped to much to keep up with consumption from lights, etc etc.

Fixed it by finding terminal on AC amplifier that was +12v when Ac & blower were switched on, fed this power to the A/C control assemble (pin 10 on the 22pin plug). This raises the revs by about 200-400 revs I think( hard to tell with a tacho that flickers around).

Oh and no gas, unleaded only

Anyway thanks for all your input guys, once again you have helped me immensely and I appreciate it!