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How to make AC work with your swap - 6G Celicas Forums

Topic #39327 59 posts Started by lagos
lagos
#31
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QUOTE(Dr_Tweak @ Jul 21, 2006 - 11:30 AM) [snapback]459053[/snapback]
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Just off the top of my head, it does look like you have everything correct. Really the most important thing is the a/c clutch circut, if that works then your a/c will work. Then we just need to make sure your engine idles up when it comes on. What year is your ECU?

-

*edit* Oh yeah, and you can pick up one of those little cans at Wal-mart or Pep Boys or whereever and fill it yourself. It's really easy, the instructions are on the can and it'll save you like $100.

-Doc



the ecu is a 1990.

i have a bottle of 134. problem is , that i the AC lines were disconnected and there is air in the system. so i need to take it to a shop so that they can put it on an electric vac pump to bleed everything out before i can refill
15PSI - 30MPG - Megasquirt Tuned
Dr_Tweak
#32
You don't actually *have* to have it vacuumed. I would give it a shot before taking it in.

-Doc
-Dr Tweak, 6GC's resident engine swap wiring expert extraordinaireClick here to see my swapsdrtweak@phoenixtuning.com
WannabeGT4
#33
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QUOTE(Dr_Tweak @ Jul 21, 2006 - 12:26 PM) [snapback]459084[/snapback]
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You don't actually *have* to have it vacuumed if you don't mind replacing the seals and/or compressor in a year or two. I would give it a shot before taking it in.

-Doc



Fixed.
Project ST204.5 99.88946% complete...
lagos
#34
IT WORKS!


i got another bottle of R134 because the one i was using was a few years old, and the gauge on it didint really sit at 0. so the whole time i thought i was over inflating it, when in fact i still had a lot of room to go. once the sensor saw there was enought psi in the system, it kicked the fans on and the AC relay. so now the AC works!

only problem is, that its not really as cold as it should be. so im still going to take it in and have it purged anyway, and refill it again. at least i got to learn all about my AC system while doing it...hahaha
15PSI - 30MPG - Megasquirt Tuned
Fastbird
#35
Lagos, with everything working, does your car idle up when the A/C is turned on??

lagos
#36
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QUOTE(Fastbird @ Jul 21, 2006 - 5:54 PM) [snapback]459227[/snapback]
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Lagos, with everything working, does your car idle up when the A/C is turned on??



no.

i have to install the idle up valve that does that. i think its somwhere in my basement. then i have to see how to wire that up and run some vac lines to it. its not a big deal tho, because the car dosnt stall out or anything, just idles a little less then it should.

This post has been edited by lagos: Jul 21, 2006 - 5:10 PM
15PSI - 30MPG - Megasquirt Tuned
lagos
#37
i did a little ghetto bleeding . fill the low side while venting the high side. it did the trick and now the AC blows ICE COLD ! its so great driving around in a turbo car will all the comforts of a daily driver.

does anyone know the exact PSI our system should be filled to? i did mine to about 35psi.
15PSI - 30MPG - Megasquirt Tuned
Aaagogo
#38
so this will be the working wiring configuration

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QUOTE(lagos @ Jul 21, 2006 - 11:19 AM) [snapback]459049[/snapback]
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plug IM1 (female) 6th gen plug that goes behind the glove box.

(pin) (where i wired it to) (what it does)

pin1 = ecu plug E8 A- pin 21 = ACT function in the ecu
pin2 = ecu plug E8A - pin 10 = AC1 funtion on the ecu
pin3 = doesn not exist on 98 harness
pin4 = st185 plug IH1 - pin 4 = this leads to the white/red wire on the AC
pin4 = st185 plug IH1 - pin 5 = this leands to the white/blue on the AC
pin 6 = II1 pin 3 = this is the tach signal from the ignitor


PLUG 2c from the ST185 harness

pin6 = EA1, fuse box plug- pin 10 = this comes from the black/white power line for the AC clutch that is on the AC compressor


i THINK thats it.

Journal for my 3SGTE swapPosting and asking qns here for my 3SGTE swapRegular on ToyotaTuners, no long on TNLurker on celictech for my 3SGTE swapTrying to sell stuff on alltrac.netTime will tell that it is a mistake to replace the F-14 Tomcat with the F-18 Super Hornet as the carriers first line of defense.
lagos
#39
yep thats how you wire it up.

you just need to look up the plug names so that you know what and where they are. all that stuff is in the toyota wiring diagram books.
15PSI - 30MPG - Megasquirt Tuned
MaskedMan
#40
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QUOTE(lagos @ Jul 21, 2006 - 7:01 PM) [snapback]459295[/snapback]
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does anyone know the exact PSI our system should be filled to? i did mine to about 35psi.


The low side pressure should be 21-35psi, and the high side pressure should be 190-220psi.
lagos
#41
whats the deal with the AC idle up valve? i see it in the wiring diagrams for the 5th gen setup, but it dosnt exist in any of the 6th gen wiring diagrams. did toyota change the way the AC idles up in the 6th gen?
15PSI - 30MPG - Megasquirt Tuned
WannabeGT4
#42
http://www.celicatech.com/vfewdsou/1995/95...ic/engcon5s.pdf


Unless something changed from '95 to '99 then:
plug E5 pin 7 "ISCV" on the 5SFE ECU controls the A/C idle up VSV.

plug E5 pin 21 "ISC" on the auto 7AFE ECU controls the A/C idle up VSV.
plug E5 pin 23 "ISC" on the manual 7AFE ECU controls the A/C idle up VSV.
Project ST204.5 99.88946% complete...
lagos
#43
ah ha! nice find.

i was looking at the AC specific diagrams and wondering why it wasnt there.

so it seams like there is a problem with adding AC idle up. on the 3sgte the idle up control is done by the AC amp.

in the 6th gen the AC amp dosnt have this function, because it is handled by the ECU.

so it seems there is no way to do it the way it is from the factory.

since the Idle up, only gets triggered when the AC clutch engages, i was thinking that maybe i can get it to work by splicing into the blac/white wire that supplies power to engage the cltuch on the AC compressor. this way, every time the clutch would come on (and make the rpm's dip down) the AC idle up would get 12v, and open its vac ports and make the car idle up. what do you guys think?
15PSI - 30MPG - Megasquirt Tuned
Dr_Tweak
#44
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QUOTE(lagos @ Jul 22, 2006 - 6:46 AM) [snapback]459388[/snapback]
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ah ha! nice find.

i was looking at the AC specific diagrams and wondering why it wasnt there.

so it seams like there is a problem with adding AC idle up. on the 3sgte the idle up control is done by the AC amp.

in the 6th gen the AC amp dosnt have this function, because it is handled by the ECU.

so it seems there is no way to do it the way it is from the factory.

since the Idle up, only gets triggered when the AC clutch engages, i was thinking that maybe i can get it to work by splicing into the blac/white wire that supplies power to engage the cltuch on the AC compressor. this way, every time the clutch would come on (and make the rpm's dip down) the AC idle up would get 12v, and open its vac ports and make the car idle up. what do you guys think?


Yes, that's exactly right. The best thing to do is actually have the clutch wire go through a relay, and have the relay switch on a VSV. The only downside to this is that it will be on all the time, even when you're not at idle. It will work though, just make sure that one side of the VSV goes to the manifold and the other side goes to the intake behind the AFM.

Good job putting it together and congrats!

-Doc

This post has been edited by Dr_Tweak: Jul 22, 2006 - 6:12 AM
-Dr Tweak, 6GC's resident engine swap wiring expert extraordinaireClick here to see my swapsdrtweak@phoenixtuning.com
WannabeGT4
#45
Couldn't you use the IDL signal from the TPS to prevent the VSV from opening when ever you're not at idle? It might be more trouble than it's worth but I don't see why it wouldn't work.
Project ST204.5 99.88946% complete...
presure2
#46
Art,
great to see you tackle this project and work it all out.
added to the sticky!
=)
Former Team 5SFTE pro member ;)13.6@108MPH, 5SFTE Powered
lagos
#47
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QUOTE(Dr_Tweak @ Jul 22, 2006 - 7:07 AM) [snapback]459423[/snapback]
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QUOTE(lagos @ Jul 22, 2006 - 6:46 AM) [snapback]459388[/snapback]
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ah ha! nice find.

i was looking at the AC specific diagrams and wondering why it wasnt there.

so it seams like there is a problem with adding AC idle up. on the 3sgte the idle up control is done by the AC amp.

in the 6th gen the AC amp dosnt have this function, because it is handled by the ECU.

so it seems there is no way to do it the way it is from the factory.

since the Idle up, only gets triggered when the AC clutch engages, i was thinking that maybe i can get it to work by splicing into the blac/white wire that supplies power to engage the cltuch on the AC compressor. this way, every time the clutch would come on (and make the rpm's dip down) the AC idle up would get 12v, and open its vac ports and make the car idle up. what do you guys think?


Yes, that's exactly right. The best thing to do is actually have the clutch wire go through a relay, and have the relay switch on a VSV. The only downside to this is that it will be on all the time, even when you're not at idle. It will work though, just make sure that one side of the VSV goes to the manifold and the other side goes to the intake behind the AFM.

Good job putting it together and congrats!

-Doc



no relay needed! and it wouldnt be on all the time. the AC clutch gets cycled on and off ever few minutes by the evap temp sensor. it dosnt stay on all the time. so 12v comes on and off to the clutch on the AC comp, while you have your AC on in the car . by simply splicing into that wire, the car would idle up at the same exact time the cluch kicks in, and idle back down to normal, when the evap sesnor cycles the clutch off. if your ac was off, then the car would act normal because the clutch idle up wouldnt be getting any voltage.

EDIT: ah i get what your saying. the Vsv would also engage while you are driving. i wonder how much this would really effect the car while its driving. since the AC comp only makes the motor idle at about 50rpm less then normal when at idle.

This post has been edited by lagos: Jul 22, 2006 - 9:18 AM
15PSI - 30MPG - Megasquirt Tuned
WannabeGT4
#48
Like I said use the IDL signal from the TPS to trigger a relay that is powered by the AC magnetic clutch signal. That way the VSV will only come on under two conditions, 1. you're at idle and 2. your compressor clutch is engaged.

Project ST204.5 99.88946% complete...
lagos
#49
yeah, your right, that would probably be the best way to do it.

do you know what kind of voltage the IDL singnal sends out at idle?
15PSI - 30MPG - Megasquirt Tuned
lagos
#50
i thought of another simple way of doing this. the basic problem is that with the AC on, the car idles too low. so you can also add the idle up in, simply by taping into any wire that gets 12v when the AC BUTTON (not clutch) is pressed. a good place for this would be to tap the purple wire that goes to the presure switch. this will make the car idle at something like 900 rpm, instead of the normal 800, and when the ac clutch comes on, it will only dip down to 850rpm and not the 700ish that makes the car idle crappy.

this way, you wont have any issues if the system making the rpm's jump up on their own while you are driving, and you wont have to mess with the TPS singal or use a relay.
15PSI - 30MPG - Megasquirt Tuned
WannabeGT4
#51
The whole purpose of the idle up VSV is to stabilize the idle when the clutch is engaged and there is an extra load on the engine. As you already pointed out, having the VSV engaged whenever the AC button is pressed will still cause a fluctuation in idle since the clutch is not constantly engaged when the AC button is pushed. A single relay triggered by the IDL signal to engage the VSV which is also powered by the AC magnetic clutch wire is probably you're best bet.
Project ST204.5 99.88946% complete...
lagos
#52
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QUOTE(WannabeGT4 @ Jul 22, 2006 - 11:26 PM) [snapback]459684[/snapback]
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The whole purpose of the idle up VSV is to stabilize the idle when the clutch is engaged and there is an extra load on the engine. As you already pointed out, having the VSV engaged whenever the AC button is pressed will still cause a fluctuation in idle since the clutch is not constantly engaged when the AC button is pushed. A single relay triggered by the IDL signal to engage the VSV which is also powered by the AC magnetic clutch wire is probably you're best bet.



yeah, your right. that is the best way to do it.

im going to try a really simple idle up, first and see how i like it. the idle only really dips down by about 50rpm when the AC kicks on. so i dont think ill have to go through taping into the tps idle signall with a relay, to get it to do what i want. i also have feeling that even if you add the relay, its going to take second for the tps to send out and idle signal ,and the relay to click on, and it will never be a super smooth and perfect setup. even on a bone stock car, the idle is never 100% pefrect when the ac is on.
15PSI - 30MPG - Megasquirt Tuned
Dr_Tweak
#53
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QUOTE(WannabeGT4 @ Jul 22, 2006 - 2:26 PM) [snapback]459447[/snapback]
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Like I said use the IDL signal from the TPS to trigger a relay that is powered by the AC magnetic clutch signal. That way the VSV will only come on under two conditions, 1. you're at idle and 2. your compressor clutch is engaged.


That's a great idea.

-Doc
-Dr Tweak, 6GC's resident engine swap wiring expert extraordinaireClick here to see my swapsdrtweak@phoenixtuning.com
lagos
#54
so here is an update....

i added in the AC idle up system and it works great. all i did was tap into the black/white wire from the ac compressor, and ran that right to the AC vsv and from the vsv to ground. it ended up working very well.

i also noticed a benefit for doing it this way vs an idle relay. before without the idle up system, if i turned the ac on while driving, i would feel a loss in power from the engine. now with the vsv working at all times, i no longer feel the drop in power. also the car seems to have about the same power with the ac on as it does with it off.

This post has been edited by lagos: Jul 29, 2006 - 8:40 PM
15PSI - 30MPG - Megasquirt Tuned
phattyduck
#55
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QUOTE(lagos @ Jul 29, 2006 - 6:33 PM) [snapback]462999[/snapback]
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so here is an update....

i added in the AC idle up system and it works great. all i did was tap into the black/white wire from the ac compressor, and ran that right to the AC vsv and from the vsv to ground. it ended up working very well.
That's a really good idea! Just make sure you turn off the A/C before you do any crazy full-throttle driving. You don't want to over-speed the compressor. smile.gif

-Charlie
2003 Subaru WRX Wagon1989 Camry Alltrac LE 3S-GTE - SV25/ST205 hybrid1988 Camry Alltrac LE - BEAMS swap started
lagos
#56
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QUOTE(phattyduck @ Jul 30, 2006 - 3:57 PM) [snapback]463229[/snapback]
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QUOTE(lagos @ Jul 29, 2006 - 6:33 PM) [snapback]462999[/snapback]
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so here is an update....

i added in the AC idle up system and it works great. all i did was tap into the black/white wire from the ac compressor, and ran that right to the AC vsv and from the vsv to ground. it ended up working very well.
That's a really good idea! Just make sure you turn off the A/C before you do any crazy full-throttle driving. You don't want to over-speed the compressor. smile.gif

-Charlie



i dont think that would be a problem. the compressor has a speed sensor inside of it that tells the ac amp wants going on. the ac amp also gets a signal from the Tach so it knows what rpms you are at. so im sure there is some type of fail safe inside the ac amp that controls all that stuff.


i have to track down a mystery noise that im hearing. i hear something rattle around when the ac is on. when i put my clutch in, or turn the ac off, the noise goes away. at first i thought maybe my throw out bearing was making noised when the car idled too low, but now thats fixed and its still doing it. maybe the ac belt is too loose. ill have to go check it out.
15PSI - 30MPG - Megasquirt Tuned
malecrod
#57
Sorry to bring this back from the dead. I have a working AC but no idle up system. I was able to source an idle up unit off of MR2oc. I read through the entire thread and the wiring diagrams. I'm new to all this wiring stuff but I kinda got most of the issues involve in wiring the idle up unit.
My question is: Is splicing into the black/white AC compressor and grounding the other wire the final solution to the AC-on crappy idle issue? I'm about to attempt this and I'm wondering what is the final word on this.
Any help will be appreciated. Thanks.
3sgteing...burns twice as bright, lasts half as long."The weight of the world is love. Under the burden of solitude, under the burden of dissatisfaction."-Allen Ginsberg-
lagos
#58
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QUOTE(malecrod @ Mar 4, 2008 - 12:02 PM) [snapback]649038[/snapback]
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Sorry to bring this back from the dead. I have a working AC but no idle up system. I was able to source an idle up unit off of MR2oc. I read through the entire thread and the wiring diagrams. I'm new to all this wiring stuff but I kinda got most of the issues involve in wiring the idle up unit.
My question is: Is splicing into the black/white AC compressor and grounding the other wire the final solution to the AC-on crappy idle issue? I'm about to attempt this and I'm wondering what is the final word on this.
Any help will be appreciated. Thanks.


Yes just splice into that black wire, or any wire that gets 12v when you push the AC button on.
15PSI - 30MPG - Megasquirt Tuned
malecrod
#59
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QUOTE(lagos @ Mar 4, 2008 - 12:13 PM) [snapback]649048[/snapback]
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QUOTE(malecrod @ Mar 4, 2008 - 12:02 PM) [snapback]649038[/snapback]
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Sorry to bring this back from the dead. I have a working AC but no idle up system. I was able to source an idle up unit off of MR2oc. I read through the entire thread and the wiring diagrams. I'm new to all this wiring stuff but I kinda got most of the issues involve in wiring the idle up unit.
My question is: Is splicing into the black/white AC compressor and grounding the other wire the final solution to the AC-on crappy idle issue? I'm about to attempt this and I'm wondering what is the final word on this.
Any help will be appreciated. Thanks.


Yes just splice into that black wire, or any wire that gets 12v when you push the AC button on.


Alright, thanks Art. I will go ahead and do that. Thanks
3sgteing...burns twice as bright, lasts half as long."The weight of the world is love. Under the burden of solitude, under the burden of dissatisfaction."-Allen Ginsberg-
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