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Engine Swap from 90 MT AWD to 92 AT 2WD - Harness Incompatible

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I am trying to put the engine from a 90 Legacy MT AWD into a 92 AT 2WD.

The main wiring harness from the engines are different.

The 90 has 3 connectors while the 92 has only 2.

 

Can I modify the harness? Where do I get the wiring diagrams? Alldata or

do I need to buy the Subaru factory manual?

 

Or could I swap out the intake manifolds too and hopefully use the old harness (it seems

to be connected to the manifold, injectors and various sensors.)?

 

Any advice greatly appreciated!

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where is the harness different? The intake manifold one shouldn't be different.

 

Look in the scans on my site for the electrical wiring and see what you can find out...... http://www.main.experiencetherave.com:8080/subaru_manual_scans/1992_FSM_(Engine_%26_Electrical)/

 

If you can't find what you need.....let me know...and I'll see if i can look in the hard copies of the manuals.

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Thanks for the wiring diagrams. They should help me get moving.

I can now be more specific about the problem.

 

My 92 2WD AT (non turbo) does not have connector E3 - it only has E1 and E2. This matches the wiring diagram as E3 is designated for Turbo.

 

My 90 AWD MT (non turbo) has E1, E2 and E3. I don't have the wiring diagram for this one.

 

Do you think I can take the 92 harness and install it on the 90 engine? There is a different number of wires so I'm wondering why and if the engine electrics are actually different.

 

Thanks again.

Mick.

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can you give me the fig number you're looking at, or which page......so I can see what you're looking at?

 

I can then try and compare that info to the 90 fsm.

 

 

 

edit: Ok....I think I know which one's you're talking about. The connectors right behind the battery....right?

 

I guess we need to figure out what goes through E3.......

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You got it. Connector E3 is behind the battery and is on Fig97.

 

The main figures that call out E1 and E2 seem to be Section 6-3 5.4 Fig 28-1, 28-2 for the non turbo. E3 is called out in Fig29-1&2 for the turbo.

 

I guess I need to find the corresponding Engine Electrical diagram for the '90...

 

Thanks yet again!

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I didn't get a chance to look at the fsm for the 90 last night......I'll try and do that when I get home today from work. I really wonder why the 90 has it, if in the 92 fsm it says it's for a turbo car.....unless it's just dummy wiring that goes nowhere.

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to be quite honest with you.....I've looked at those diagrams and I got to be looking at things wrong....or incorrectly. I think I see where the connectors are....but don't know how they're referenced to the fold out pages where they show where the connector is.

 

Even on the 90 FSM's......it really didn't show me anything.....granted I may not be looking at things correctly?

 

Got a quick lesson on how I should be looking at these electrical diagrams.......

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Josh,

 

Someone told me that the local library has a subscription to Alldata so I just got back, after printing the engine wiring diagram for the '90.

 

I am looking at Fig 28-2 from the '92 manual I downloaded from your site.

 

It appears the '90 E3 connector was done away with and the wires were routed through '92 E2. "Most" of the other wiring is identical so I might try rewiring it. Hopefully the "minor" difference don't catch me out!

 

I don't know if I answered your question about how to read the diagrams though... The E connectors are shown on the top of the page and the mating F connectors shown at the bottom of the page show how the wires match up with the connector.

 

Thankyou very much for your help, and the downloads!

 

Mick.

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why not just switch the wiring harness from the intake manifold? It's pretty simple to take off.

 

I'll have to look at the diagrams again.....I'm beat now....just got done cleaning the house.....

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I probably will just swap the harnesses. I was afraid there might be more differences but it doesn't appear there is.

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