A/C into 89 EFI Touring Wagon

wagonist · Post by **wagonist** » Sun Nov 15, 2009 5:41 pm

I'm converting my 88 touring wagon to EFI.

On the carby engine, the idle up for the A/C is done by a vacuum solenoid that activates the throttle slightly.

On the EFI version, I can see there is no provision for this and am guessing that this function is done by the ECU opening the idle valve.

For the ECU to get the A/C on signal, I need to check where the "dealer fit" Oz A/C loom connects (if at all).

The only thing I can guess is that up behind the fusebox there is a pair of blue/yellow wires into a single pin plug.
This is a matching plug to one on the A/C loom in a similar position (Blue wire which I know is the A/C on signal from the switch).

Am I correct in thinking that these plug together?

YouTube · Post by **El_Freddo** » Thu Nov 19, 2009 4:23 pm

AC wiring between carbie and EFI is always messy. I never got my AC going while I had my MPFI EA82 in the place of the original carbie unit. Now that I've got the EJ installed I'm aiming to have the AC operational again. I've just gotta work out how to do it.

The easiest way for you to do it would be to grab all of the AC wiring plus anything that wiring connects to - including the condensor box under the dashboard which means opening up the system and losing the cooling gas. You'll have to make sure it is the same wiring as that of the EFI wiring from the same subi. You might need the AC pump too.

This is just the way I think about things like this, I'm sure there is a way to get around it. I know there will be a little blue single blade plug that the AC wiring should tap into. The other wires you're talking about will most likely be a switch on the dash to trigger the system. I'm not sure if the EA MPFI system needs a wire to tell the ECU to open up more on the idle control or not, it may do it automatically under the load of the AC pump in operation.

Hope this is of some use.

Cheers

Bennie

Gannon · Post by **Gannon** » Thu Nov 19, 2009 4:48 pm

I put an MPFI loom in my l series and i used the carby air conditioning wiring. There was a plug taped back above the fuse box that plugs into a similar plug in the mpfi loom, so what you have described is probably right.

YouTube · Post by **El_Freddo** » Thu Nov 19, 2009 5:05 pm

That might explain why my AC now has power when I push the AC button - at least the button lights up, I haven't checked anything else in the system to verify. That's a task for ron but hopefully it won't take much to get it up and running again, AC would be a real luxury especially since I've got the EJ to power it AND the subi at the same time

Cheers

Bennie

wagonist · Post by **wagonist** » Thu Nov 19, 2009 9:44 pm

Is this the plug you're talking about, Suparoo (see attached)?

White one is the A/C loom & blue one is the car.

They seemed way to close to be just convenient.
And the A/C loom is desgined for both RHD & LHD, so there was another plug in a similar position on the left side.

El_freddo, if you're runnig the dealer fit A/C (like all Oz L series got), then it should run independant of whatever wiring & engine is in the car, except:
The EFI needs a single in to know the compressor is engaged, & therefore to increase the idle
The L series has 3 prongs on the front of the compressor, which the EJs don't have. Somehow this signal needs to be retrofitted to the compressor (I have seen it done) otherwise the A/C won't run.

Gannon · Post by **Gannon** » Fri Nov 20, 2009 5:03 am

Blue wire? i think thats it. Its been a few years since i did mine but it looks right.

Its been a while since i have seen you on here Wagonist. I thought you abandoned your 88 WRX touring wagon project. Good to see you back.

wagonist · Post by **wagonist** » Fri Nov 20, 2009 8:15 am

The wire's in too convenient a spot to not be it.

There's been no interest in buying my parts, so the WRX part of the conversion has been ditched, so it's now got an NA EFI EA82 & part time 4wd box (though I'm trying to get hold of my old full time 4wd dual range, centre diff locked box), interior is off at the trimmers at the mo to get the black RX turbo trim modded to fit the wagon, & it'll soon be off getting a pait job.

Then I'll decided whether to keep or sell it (unfortunately it doesn't suit any of my purposes any more:()

discopotato03 · Post by **discopotato03** » Fri Nov 20, 2009 8:24 am

The MPFI engines throttlebody has a solenoid valve called FICD which I think means fast idle control device . This is separate from the idle speed by pass screw and passage but the FICD also has an adjustment screw and its own passage .

From my 87 WSM it simply says it switches when the blower fan and compressor are selected .

In the wiring diagram it is linked to the Rad Fan Relay and the Air Conditioner Relay and I think via earth switching of the Blower Fan Relay .

I STRONGLY suggest you replace any water lines that the AC compressor and its garguantuan bracket cover up because they are difficult to get at once the mongrel is in place . Mainly the 90 deg rubber hose off the top of the water pump . The steel pipe behind it has a bad habit of rusting through and giving pin hole leaks . Do not run straight water in an L cooling system if at all avoidable .
The bracket has another tensioner for the second or inner fan belt that AC cars have and its a mongrel to work with as well .

The compressor/bracket assembly is heavy and don't be at all surprised if the height of your cars nose drops a little .

I removed my cars AC gear because I was having cooling problems at the time and hated the lack of space to work on these cars with it . I reckon too many things you can't get at , too much weight , engine cooling was my no1 priority .

A std long in the tooth L , even a turbo one , isn't exactly a powerhouse so any parasitic loss is easily felt .

Cheers A .

wagonist · Post by **wagonist** » Fri Nov 20, 2009 9:31 am

The compressor won't turn on until both the A/C switch & the fan blower are on.
The A/C loom has a spur wire off of the compressor clutch signal wire which has been the one I've been querying.

Soemone else suggested to me that connecting the compressor wire to that fast idle solenoid also works (it's just a magnetic plunger either open or closed).

I've had to pull of the inlet manifold to change the power steer bracket (engine was from a Vortex), so I'm intending to change those hoes, etc whilst it's apart, including the bitch on that goes from the thermostat down to the block under the manifold.

Cooling problems are easily fixed by proper radiator maintenance.
And it's not that hard to remove the A/C from the engine. Sure it's tight, but it's not like it takes several hours.

The reason the WRX bit got deleted is that I couldn't fit the larger radiator, fans, A/C core & intercooler radiator in the nose.
And with the recent weather, there's no way the A/C is being removed.

discopotato03 · Post by **discopotato03** » Fri Nov 20, 2009 12:05 pm

Well I put a brand spankers OEM standard Japanese Koyo radiator in my RX and let me tell you it could have more cooling capacity .
The engine and water pump/hoses etc are all effectively new and the only way I can make it livable is with a larger not std thermostat and a Davies Craig switch to make the condenser fan cut in at a lower temperature .

Still isn't happy in traffic .

A .

Actually just about to fit the Tridon large valve 170 deg themostat in place of the 180 deg one .

Just in case you want the part no's for the large valve versions :

TT2041-170 , TT2041-180 .
I always use their Ea81 gasket pt no TTG15 .

I never could confirm but I think these large valve versions were std on Spider Vortexes and two of my three Spiders had them but in an OEM brand .

YouTube · Post by **El_Freddo** » Fri Nov 20, 2009 12:45 pm

wagonist wrote:El_freddo, if you're runnig the dealer fit A/C (like all Oz L series got), then it should run independant of whatever wiring & engine is in the car, except:
The EFI needs a single in to know the compressor is engaged, & therefore to increase the idle
The L series has 3 prongs on the front of the compressor, which the EJs don't have. Somehow this signal needs to be retrofitted to the compressor (I have seen it done) otherwise the A/C won't run.

Hehehe... This is where I have my bit of fun! My MY is 1988 where there are a few different bits under the bonnet that are from the factory - like my AC compressor without the 3 prog thing on the pulley, there's only one wire from that area and its green, I'm sure this is the clutch control wire... I can get you a pic of the old AC compressor in a couple of days if you'd like to see it

discopotato03 wrote:The compressor/bracket assembly is heavy and don't be at all surprised if the height of your cars nose drops a little .

I doubt that at all - with the EJ installed I've not noticed any drop in the front end, I'm yet to check it with a tape measure to compare to the EA motor's suspension height, but from eye there is nothing noticable in height difference...

wagonist wrote:The reason the WRX bit got deleted is that I couldn't fit the larger radiator, fans, A/C core & intercooler radiator in the nose.
And with the recent weather, there's no way the A/C is being removed.

Fans I can understand if you're going for factory. I've got a 3 core radiator, one modified fiori thermo fan and an EJ installed in my L series. Its very tight in there and I'm now thinking of using some EA engine mounts in the front EJ engine mount hole to push the EJ motor and gearbox back. The gearbox crossmember mount holes need to be slotted backward and the tailshaft may need to be shortened by the corresponding amount. Its something I'm looking into at the moment as tight turns in low 4wd will have the PS pump kiss the shroud on the thermo fan, which means that 5mm clearance is defently not enough...

AC, can't wait to have it for once! I've gotta get a condensor raditator for out front cos my old one is clogged and now outta shape.

Cheers

Bennie

wagonist · Post by **wagonist** » Fri Nov 20, 2009 2:18 pm

I had a custom twin core radiator made (2 L series cores), so it was damn thick.
I've given some serious consideration to having the pipes cut off (they were made to suit the EJ20T motor) & having the L versions installed instead.

Then it'll never have a cooling issue, though admittedly I'm a A/C on for couple of mins to cool car type person, then I just wind the windows down.

Gannon · Post by **Gannon** » Sat Nov 21, 2009 6:39 am

The US got twin core radiators in their EA82T's. I tried to source one but the guy at the local radiator couldnt get them and i didnt have time to chase one from the US and get it posted.

So wagonist, did you plug them in and it still doesnt work?

wagonist · Post by **wagonist** » Sat Nov 21, 2009 6:30 pm

Don't know as yet.
Inlet manifold isn't atached to the engine at the moment.
Nor is the rest of the A/C installed, but hopefully that will change by the end of next week.

wagonist · Post by **wagonist** » Mon Nov 23, 2009 10:53 pm

Next question:

tacho signal for the A/C, where does this come from?

On the carby versions, and the series 1 EFI's, there's an extra wire haning off the coil, but it seems that the later EFI's get there tacho signal from the distributor (ie cam sensor).

On the car I stripped the loom out of, I didn't notice a wire for the A/C hanging off the coil.
Doesn't mean I can't do this though;)

Gannon · Post by **Gannon** » Tue Nov 24, 2009 3:59 pm

It shouldnt matter what model, they all should work the same way

Im assuming you are refering to the yellow wire that goes from the negative side of the coil, to the pulse amplifier

wagonist · Post by **wagonist** » Tue Nov 24, 2009 7:20 pm

Yeah, that's the one, basically the tacho signal.

I'll just retrofit something. Ain't hard.

Just discovering how much Subaru changed for the series 2. ie tacho signal comes through the driver's side of the dash. Which really fun when changing the loom over onto the black series 1 skin & discovering someone had chopped off the headlight wires plug:mad: Lucky I had trhe original carby dash loom still to massacre.

I'd really love to hide the A/C wiring from the engine bay, but it's a bit of a hassle.