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I am hoping someone can briefly answer this accurately. I took the harness for ecu out with minimal snipping. I can literally plug in from intake harness and go all the way to ecu with many unsnipped wires. the ones I snipped were entangled and shared off to something else. Coincidentally all the shared ones were either yellow with a stripe or solid black (ground- again shared grounds :mad:) or black and white stripe (power?). I was putting the pieces together and realized I don't need quite a few things for my swap onto a carbed GL. this is what I do need and have nearly uncut for oem harness.

fuel pump relay and yet 2 other relays (assuming the clutch switch to start and ... ?)

 

all SPFI gadgets and unit - tps, thermistors, oil , and even maf (the longest cable)

 

spfi distributor, the gadget underneath coil, and coil

 

the black and white wire that goes into fuse box (is that the only power for the ecu?)

 

 

So, in conclusion my guess is that it is easier to put this retrofit together than originally thought as long as engine will turn over without the clutch safety switch and even then I would hack it. Am I missing something? I saw a few threads about this and successful with the ej swap. What I am doing should be easier- I am optimisticly thinking.:) The fuel pump stuff is tricky. I will no doubt need the crazy map diagram from manual. I am pretty sure I cut that right out and will have to wire in. The other shared stuff is for dummy lights mostly. One of the shared wires snipped is for the fuel stuff no doubts. It is my only slight worry.

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You shouldn't have "snipped" anything till you took the entire harness out of the donor. And even then there is very little cutting to do. Now it's going to be a real mess to figure out, as you probably don't have the dropping resistor for the coil, the diode pack under the dash, or the connector pin for the start signal from the ignition switch.... and maybe a mess of other things I can't remember right now. It's best to remove the ENTIRE harness from the vehicle, and sit down with the connector pin-outs and some wire cutters and carefully dismantle it. It's not as simple as looks.

 

Snowman created a whole manual for this swap, and he and I are working to correct a few things, and add some EA81 information for version 2 of this document. Since you are doing an EA82, basically all of the information you need is here:

 

http://www.mnchopshop.org/images/offroad/subaru/spfi_conversion_manual.pdf

 

One thing I can tell you that isn't in the manual (yet), is that the Loyale ECU (the silver boxed version - older units were painted black) has some different programming, and requires both the neutral switch, and speed sensor to be connected or it will refuse to return accurate diagnostic data, and will not idle properly.

 

BTW - you did get the oxygen sensor harness right? And you will need the 02 sensor in the exhaust of the new car.

 

GD

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You shouldn't have "snipped" anything till you took the entire harness out of the donor. And even then there is very little cutting to do. Now it's going to be a real mess to figure out, as you probably don't have the dropping resistor for the coil, the diode pack under the dash, or the connector pin for the start signal from the ignition switch.... and maybe a mess of other things I can't remember right now. It's best to remove the ENTIRE harness from the vehicle, and sit down with the connector pin-outs and some wire cutters and carefully dismantle it. It's not as simple as looks.

 

Snowman created a whole manual for this swap, and he and I are working to correct a few things, and add some EA81 information for version 2 of this document. Since you are doing an EA82, basically all of the information you need is here:

 

http://www.mnchopshop.org/images/off...ion_manual.pdf

 

One thing I can tell you that isn't in the manual (yet), is that the Loyale ECU (the silver boxed version - older units were painted black) has some different programming, and requires both the neutral switch, and speed sensor to be connected or it will refuse to return accurate diagnostic data, and will not idle properly.

 

BTW - you did get the oxygen sensor harness right? And you will need the 02 sensor in the exhaust of the new car.

 

GD

 

I got the exhaust stuff and wires near tranny with distributor, all one shot. along with all the coil stuff. the speed sensor stuff wouldn't be on a carbed dual range tranny version correct? use tach instead? I guess this makes a problem. The whole harness is there with all the little thing under the dash.99% unsnipped, pulled the whole tangled mess out. Thanks for pdf, will be looking it over-- oops that link didn't work.

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I beleive all EA82s had a speed sensor in the dash. It was used for the Cruise Control.

 

At least my brother's 87 w/out cruise still threw a CEL when the speedo cable broke for the Vehicle Speed Sensor.

 

Correct - same for all Subaru's from 1982 on. 80 and 81 EA81's do not have one. All cars were equipped in case the dealer wished to install CC.

 

The speed sensor is part of the guage cluster. It's a pulse signal generator atached to the speedometer. If you have cruise control, you can track down the CC computer, and tap into the speed sensor signal line from there, but if you do not, you will have to remove the guage cluster to get access to the plug. On the EA81's the speed sensor has two wires - the black one must be grounded. I'm not sure of the EA82 is self-grounding or not.

 

Sorry - thought I got the right link - there's like three or four links floating around for it. :rolleyes: I fixed it so now both work in the thread.

 

GD

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That info was excellent. It is a can do. So now i will be making a loyale with dual range 3 years older than the oldest loyale in a GL. I do have to be sure the old gl is good enough first. Thanks alot for info. If/when project is achievable, I will post on web photos etc. I have some First things first ... projects later.

,My only worry was speed sensor, and the info answered that q, all ea82s have one. The neutral switch isn't even necessary

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No - it's not that simple. The ECU looks for changes in the neutral switch corresponding to changes in the speed sensor. It takes a little while for the ECU to catch on, but basically if you are moving and the neutral switch continues to report you are in neutral, the ECU assumes something is wrong after a while. It won't do it right away as it doesn't want to complain about coasting, etc. But it will get angry, and when it did, it prevented the ECU from reporting the idle air code, and the purge solenoid code on mine - not cool.

 

You would have to wire a switch to the dash and toggle it each time you let the clutch out.

 

I really don't know why anyone would *not* install the switch - it takes about 10 minutes, and it's just one wire to the ECU and a ground. It's not like it's a huge deal or something. It's equipped on all cruise control vehicles for the cruise control, but unlike the speed sensor, it only exists if you really do have cruise control (or SPFI).

 

GD

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If you don't connect the neutral switch, the ECU will throw a code about it, and your CEL will be on all the time. This also causes the computer to ignore other potential problems. It's best to connect everything.

 

GD

 

If I don't need it won't use it. been lookin at cel since i started this car 18 months ago about egr solenoid.it is kicking on exactly what I don't want anyway. the actual computation of injection is all it needs, it has no problems or changes with cel light on. My friend informed me of his toyota automatically going into a fail-safe mode when a code triggered in it. The loyales Ecu's do not do this.if it is supposed to, it isn't obviously happening, the mpg was great. Thankfully. :) My 2wd sailed right into the 30's mpg no matter what little thing i did to change stuff. I am looking forward to the thermal readings lower allowing for a bit more performance in the gl, without a/c pump clogging the intake and airflows externally. Every little thing I did on the loyale made a difference after one trip- ecu was learning.the gl with more lugging at the engine ought to be a nice retirement for the 2wd spfi- much slower curve air/fuel/torque/temperatures and top end, take off snap hardly likely..:headbang:

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The CEL is there to detect REAL problems. It won't even light up for most small things unless you put the system into D-Check. The only time the CEL will light while not in D-Check mode is when the ECU goes into open loop operation, and "driveability" is affected. Here's a quote from the FSM for you:

 

"The U-Check is a user-oriented mode in which only the SPFI components necessary for start-up and drive are diagnosed. On occurance of a fualt, the warning lamp (CHECK ENGINE light) is lighted to indicate to the user that the dealer's inspection is necessary. The diagnosis of other parts which do not give significant adverse effect to start-up and drive are excluded from this mode in order to avoid unnecessary uneasiness to be taken by the user."

 

The EGR sets it off not because of driveability concerns, but because the bunny huggers and the EPA mandated that the driver be warned of failures in the emissions systems.

 

Not hooking up the neutral switch is stupid - it's extremely simple to do, only requireing the drivers plastic kick panel to be removed, and two wires soldered. The CEL will light without it every time the car is driven, and because you "think" the CEL is refering to the neutral switch, you will never bother to look at the codes, and could miss indications of impending failure of more important parts. The CEL is a warning and safety device. It's there to provide valuable feedback to prevent possible damage to your engine. Ignoring it because you *think* you know what code it's telling you about is just as ignorant as driving without your seatbelt on the wrong side of the road.

 

And regardless what you "think" the EGR does, it's entirely passive. The EGR does not rob power, and there is nothing wrong with leaving it operational. Besides that, the solenoid code from the ECU is only telling you the solenoid itself is bad - it does not indicate anything about the EGR valve itself. You can replace the solenoid with a resistor and never have to look at that code either.

 

GD

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The egr is bad news for me. from an 87 dl to the gl I just got and even on the 93 spfi.I gained over 10mpg the very day I unhooked it. of course my egr valve was bad, and I did get minimal wifs of engine in other loyales with same setup. my 87dl was untouched as far as egr, because I opened the exhaust (carbed anyway- here in maine i didn't even need the convertor). I would really like to blame frigid ground temps, but it does it all year round. Beyond odors, things electrically start failing even in the car. like the clock etc. "EGR PIG" isn't even something I made up.. it was happening to alot of subes, and even other makes and models. The top end heat has got to go!

The cel light is great. Maintaining on my own gets a real check at ecu .I don't need it.

I like the thought of ECU doing less work with wiring in terms of many feet less, the accuracy could only be better by timing and no place else to go like a pc and its complete circuit. I am keeping the y-pipe from the spfi car too, so no drilling needed. While it is out I can put the bosch o2 sensor in.The directions you led me to are excellent. the other problem I was thinking of was the fuel relay, it is actually easy to tie it in according to directions. The one difference I would do rather than straight to battery for a circuit and adding fuse on my own, is use a circuit existing in the car. ECU isn't much of an amp draw after it drops its own volts, and can have a fuse on a circuit labeled like a normal spfi would. I was thinking the dash clock. It even has an ignition source, and can use regular fuses in a regular place (the fuse box). Other than that, what the writer wrote is easy to understand- including arguments for neutral switch. I drove a dl for 8 years with no switch, reminded me of an older vehicle, but it was no big deal.

Will be awhile for this to get put together. I may run cabling soon and label it, so day(s) of swap will be much less to do. I don't have a garage handy btw, so this cooler weather climbing in fast is not good for the retrofit.As it is I am tearing down an old sube in a rental apartments driveway (again! -same chore different place!) :grin:

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One of the corrections we are going to make to the manual for version 2 is to clarify the part about the neutral switch preventing the car from being started in gear. That's the job of the automatic transmission "inhibitor switch". I have the neutral switch installed in my Brat with SPFI, and I can start it in any position. Clutch in or out does not matter.

 

For the car you are working on, it's not going to prevent you from starting it in gear - that part of the manual is mistaken I'm afraid.

 

The neutral switch is there so the ECU knows when the car is in gear and can adjust the timing and fuel maps accordingly. It WILL affect your mileage - as stated in the quote I gave you above, the CEL will only light in U-Check when a component affecting driveability fails it's test parameters.

 

Additionally, the ECU may never tell you about other system failures. It expects you to fix U-Check codes immediatly, and it's self-diagnosis programming will terminate as soon as it sees the neutral switch is missing or non-operational. Thus if you idle air control valve fails, the ECU will never tell you about it because it can't get past the neutral switch warning. By not installing everything as it was intended, you are circumventing the ECU's programming. Without downloading the EPROM in the computer and actually understanding every detail about the self-diagnostic procedure you are working blind. Don't mess with what you don't understand. I'm a software engineer, and I'm telling you it's very important to hook everything up.

 

GD

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Thanks for all the new information, GD. I'm going to try to compile an addendum to the manual with all the stuff GD found when doing his swap and get it posted in the USRM.

 

If it helps at all, when I was figuring out my swap, I stripped off all the electrical tape and conduit from the wiring harness, laid it all on the ground next to the driver's door, and started hooking stuff up that I knew I needed. After I had everything connected and had started the car, I cut off everything that was still sitting on the floor, and I was done.

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reading the entire fuel injection chapters of the FSM a couple of times, and getting to know the material well also helps. Reading two different companies' description of both an SPFI and an MPFI system, and youve pretty much got the basics of EFI systems down pat.

 

you got the FSM bgd? its in chapter 2, section 7. its page 11 of the second of the two pdf file fragments that float around here. good stuff, man.. should make all the best-seller lists.

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One of the corrections we are going to make to the manual for version 2 is to clarify the part about the neutral switch preventing the car from being started in gear. That's the job of the automatic transmission "inhibitor switch". I have the neutral switch installed in my Brat with SPFI, and I can start it in any position. Clutch in or out does not matter.

 

For the car you are working on, it's not going to prevent you from starting it in gear - that part of the manual is mistaken I'm afraid.

.......

The neutral switch is there so the ECU knows when the car is in gear and can adjust the timing and fuel maps accordingly. It WILL affect your mileage - as stated in the quote I gave you above, the CEL will only light in U-Check when a component affecting driveability fails it's test parameters.

......

GD

 

the ecu will go with what is happening by other measurements, pushing in clutch to change gears will change speed sensor, as it is hooked up to the tach.neutral switch should be unnecessary. Another note aqbut neutral swirch-- my clutch had to be nearly to the floor to start car, changing gears down the road, doesn't even meet the neutral switch. Definately unnecessary.That is for forgetful people like an auto seatbelt. No nuetral switch has its benefits , bad clutch and needs to start in first.. or maybe your racing an electric rc car and you could only use the starter to turn engine to make it fair :grin:

 

So far, after glancing at harness, it will be a lightweight in comparison to oem after some stuff is removed. Maybe for cel, a different location in a spot not bothering me would be decent. I did mention wanting to use the clock circuit after pulling the clock, for the ecu battery/ign sources maybe put a light behind the tinted part of clock holder- make it barely noticable, but still there. I will not have that crazy egr valve in this gl either, so light will be on at all times anyway. thanks for help on this. The fuel stuff left me stumped, the manual really had written what I was after, as well as the speed sensor behind dash cluster.His description of neutral switch was good too.

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I give up. Ruin it if you must.

 

GD

 

hey the fsm for an 89 is indeed different. Color codes and placement. I will be getting the 93 fsm on ebay- claims to have diagrams. there is eleven things needed to get it to run properly, the rest can go in a dumpster for all i care. :grin:

The biggest mess was all the sharing of grounds(OEM connectors are very cheap- pinching a bunch of grounds into this flimsy clip). the power was not all that difficult to figure out. Not memorizable, but not that difficult to me. Get pumped up, slam it all together, cram it under the dash and hope for the best.....:burnout:

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I was tugging at stuff gently to get the tangled mess out and pulled a wire from a 4 way splice (grounds), much like photo. Jeesh, couldn't they cheat with a butt connector?! how cheap of them. On a technical note I figured something out about how they wired them. It seems they changed things (coincidentally?) in a pattern of 1 year the same, then 2 years, then 1 year yet again, then 2 years, and I am an unlucky one with a 1993-1994 unique for the last year. So.. anyone have a 1993-1994 Loyale wiring diagram?

 

subarusplicebc2.jpg

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1. It's not cheating.

 

2. That is better than a "butt splice". You'll notice that the wires have no corrosion at all. The electrical tape sealed it from oxygen, and using a copper clip with copper wire prevents any dissimilar metal reactions. It's actually a very effective, effiecient way to build a harness.

 

GD

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I trust the splices. I will be using another means due to untangling, snipping, rerouting, leaning out what I don't need. It should be much shorter route for radiator thermistor and maf than in the loyale.

I really need a 1993 diagram. the manual I was lead to is wrong year. There is some other things tied into ecu for 1993 including 5 way splices with end points unknown. I could only guess auto seatbelt. The ecu was just for fuel injection right? why am i finding this other stuff? I hope to ignore it with a diagram. chiltons did good with the 1990-1992 . does anyone have a 1993? macro pic or scan fuel injection or engine electrical section? :)

 

there was also a/c idle kicker and whatever else. won't need it

 

if your book has wiring color codes that match this photo it is correct for my intentions

http://www.ultimatesubaru.org/photos/showphoto.php?photo=13242&size=big&cat=recent&limit=recent

 

that is connector f 108 for spfi ecu 1993 loyale 2wd

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For what it's worth, my haynes manual shows the same diagram for "1990 - 1994".

 

All my FSM's are EA81, so I am just as blind unfortunately.

 

GD

 

I ran into same stuff with haynes. My radio install was impossibled for same resaon as my ecu stuff.Color codes way off and even plugs and paths. I need a specific year and model info. I can decipher alot of it, but there is positives and negatives and the a/c stuff.

I am keeping an eye on ebay. they got FSMs on cd once and awhile.:)

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Just my thoughts:

I've done this to two cars now, my 87 GL SW and a 84 BRAT. Both times I was really lazy so I built a harness from scratch Vs pulling the whole thing:lol: I also never hooked up the neutral switch OR the speed sensor. The cruise works in my SW still. I also drove my SW for about a month without an O2. it got marginal MPG and smoked going downhills:-\ I used the wiring diagram found in the addendium of my Haynes manual. I used parts from a 94 loyale on the SW with a fuel pump from a turbo wagon... on the BRAT I got mystery parts from zeke's wagon that I dont remember the year of.... but hey, free parts:banana: On the wagon I used all 14 gauge wire, which made the harness HUGE. On the Brat I used mostly 16 gauge wire, which helped and 14 for the power and other major wires. On Ricks XT wagon I used 18 gauge wire with 14 gauge mains, this worked best for harness size and useageynessdom.:rolleyes:

ok then

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