91 Legacy ECM, Fuel Rail,Injectors Swap from 92 Lega

[none77]

Hello Everyone!!

I'm super excited that I finally found a 1992 Legacy that was being parted out.

I got ECU, Fuel rails and injectors. I have read lots of posts about doing this. I noticed a couple of the posts mention swapping connectors for injectors.

To my untrained eye, the connectors on the Red Top injectors look identical to my Grey top injectors.

Can someone confirm what needs to happen with connectors before I start.

My plan:

-install 92 Fuel rail and injectors on my 91 intake. Use spacers if they are present on 91 when I remove existing Fuel rails.

- Plug in red top injectors to existing connectors.

-Install 1992 ECU

Get super excited that my car is running properly, after spending all summer trying to diagnose problems.

[Legacy777]

The electrical connectors for the injectors are identical. Just swap the injectors, rails (spacers if needed) and the ECU.

Is your 91 an auto or manual trans? If it's a manual trans there are differences in MAF sensors and I believe IAC valve. You must run the black plastic JECS MAF if you run the 92 ECU. If the IAC valve is different too, that may present an issue....however I'm not 100% sure.

The other thing to note is the AT/MT identifier pin is wired backwards on the 92 ECU. I found this out when I swapped it in. Depending or not whether you are currently MT or AT, you may need to snip the wire going to that pin or add a wire to ground that pin.

[none77]

My 1991 Legacy is Automatic.

The 92 I took the ECU from was Automatic.

Do I need to solder or clip ECU?

I'm such a noob, I don't even know where the IAC valve is located.

I still have access to the 92, but it's over an hour away. I'm planning to go back and remove tow hitch. I could get teh IAC vavle, if I know where to find it.

[none77]

I found some pictures online of the IAC valve, and I removed it when I was taking the TPS. I have the IAC valve from 92, but it looks the same as the one currently on my 91. Is it different internally, or should I just swap it?

I worry that everything plastic and rubber is fragile on cars this old. I broke the plastic t fitting in the hose that connects PCV vale this summer, and had to go salvage yard to find replacement. I tried to get the plastic T off the 92 I was getting parts from, and broke it by accident.

Is the ECU wiring for MT or AT being differnt from 1991, unique to 1992, or does it apply to 92-94?

Thanks for all the advice. This forum, is a lifesaver with all the information & knowledgeable people.

[Legacy777]

Sorry for the late reply.

Since your car is an automatic, that makes things much easier as it already has the JECS MAF and same IAC valve. You will just need to swap the rails, injectors, (spacers if needed), ECU, and snip the wire going to the ECU's connector B48 pin 20.

This link has more info and some wiring diagrams.

http://www.surrealmirage.com/subaru/swa ... l.html#ecu

[none77]

Awesome, Thanks for all the info!

[Legacy777]

You're welcome. Just post if you have questions.

[none77]

I finally swapped Injectors, Rails, and CEl. Car is running great!

Thanks For all the Help!

[Legacy777]

Glad to hear it's running great!