Adapting an EJ20G ECU

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rob
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Re: Adapting an EJ20G ECU

Post by rob » Thu Feb 10, 2011 10:09 pm

I updated the ignition part again.

-Rob

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Re: Adapting an EJ20G ECU

Post by DevC » Wed Jul 18, 2012 3:10 am

Works great, thank you for the writeup!!
93 Turbo Wagon, 5mt swap, vlsd, sti slanty, vf10, alk, subframe lockout, gr2's, sti sways.
96 F-350 CCLB Powerstroke
89 Volvo 244, lsx swap

rob
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Re: Adapting an EJ20G ECU

Post by rob » Wed Jul 18, 2012 5:34 am

good to hear. Thanks for the feedback.

logan9691
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Re: Adapting an EJ20G ECU

Post by logan9691 » Mon Jan 28, 2013 3:44 am

So with the pin47-6 purge control being removed from this ecu, do you think it's possible to remove the charcoal canister to help free up some room under the hood?
VF43 custom FMIC APEXI intake Invidia 3" TBE JDM Ver. 4 RA STi trans (4.44) SPT short shifter rear LSD WRX rear axels coilover suspension JDM 4-pot front brakes drilled slotted rottors Greddy EBC tuned 20G ECU sti 550cc injectors Jecs MAF walbro 255

mike-tracy
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Re: Adapting an EJ20G ECU

Post by mike-tracy » Mon Jan 28, 2013 8:04 am

It is possible. I run a 2-port N/A canister instead. It could be my imagination, but the car seems to run better with it connected.
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote:
Mon Jan 14, 2002 10:23 am
Wait....I'm confused now.

Legacy777
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Re: Adapting an EJ20G ECU

Post by Legacy777 » Mon Jan 28, 2013 3:56 pm

Yeah, I'm running a 2-port non-turbo canister and haven't had any issues.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm

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Re: Adapting an EJ20G ECU

Post by logan9691 » Mon Jan 28, 2013 7:24 pm

No, I'm talking about taking the canister out completely. Whether its 2 port NA or 3 port turbo the damn thing takes up equal amount of room. If the purge solenoid isn't being used, what's the point of having it?
VF43 custom FMIC APEXI intake Invidia 3" TBE JDM Ver. 4 RA STi trans (4.44) SPT short shifter rear LSD WRX rear axels coilover suspension JDM 4-pot front brakes drilled slotted rottors Greddy EBC tuned 20G ECU sti 550cc injectors Jecs MAF walbro 255

wtdash
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Re: Adapting an EJ20G ECU

Post by wtdash » Mon Jan 28, 2013 8:27 pm

Josh replied to your otherpost:
Legacy777 wrote:You can remove it, but pressure will build up in the gas tank. The normal hiss you hear when opening the cap will become a hisssssssssssssss. I'm serious. I didn't run the canister for a while and at fill ups it hissed for a ridiculously long time.

Does the 20g ECU have any canister purge control pin? If so, I'd just repin that pin.
Turbo Subies:
'87 GL-10 Turbo 4WD Wagon (pre-Loyale) - SOLD
'90 BJ, EJ22T/DOHC and 5-speed swap - SOLD
'04 FXT, Forged internals, VF39, STI TMIC, Cobb AP- SOLD
'93 Legacy SS - 5-speed, SOLD :-(
'02 WRX GG-SOLD
'96 BD - turbo'd-SOLD

Dynamic Entry
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Re: Adapting an EJ20G ECU

Post by Dynamic Entry » Tue Jun 30, 2015 9:26 am

Legacy777 wrote:The MT harnesses should not have a wire there. If they do, I'm not sure where it would go. It should not be grounded though.

It's an input to the ECU. Grounding that pin tells the ECU whether the trans in the car is MT or AT. The ECU will alter idle speeds/loads and timing to properly adjust idle. There may by some additional minor stuff that the ECU changes, but I don't really have any info on that.

Subaru apparently put both sets of info/code into the ECU. When I did my AWD & 5spd swap, I was using my 90 AT ECU hooked up to a MT. All I had to do was snip that MT/AT identifier pin. Everything worked great.

One thing to note. The later first gen non-turbo legacies 92+ apparently had reversed AT/MT identifier pins. They were reversed from what the 90-91 MY's had, and were incorrect when compared to the factory manual. However, that issue does not affect the turbo ECU's, all years 91-94. I bring this up in the event someone is swapping in a turbo motor into a 92+ non-turbo legacy and keeps the existing harness.
rob wrote:Thanks for the insight Josh. I removed the AT/MT pin concern from the list.
I have a 93 SS that was an automatic and has been swapped to manual. What does this mean regarding the MT/AT pn in this specific case.
Andrew

02 WRB WRX
93 White SS "Angel": 4EAT to 5MT 550 Robtune !SOLD!
̶9̶2̶ ̶W̶i̶n̶e̶s̶t̶o̶n̶e̶ ̶S̶S̶ ̶5̶M̶T̶ R.I.P.

wtdash
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Re: Adapting an EJ20G ECU

Post by wtdash » Wed Jul 01, 2015 5:39 am

Dynamic Entry wrote: I have a 93 SS that was an automatic and has been swapped to manual. What does this mean regarding the MT/AT pn in this specific case.
Should not be an issue.

Are there any issues w/your car related to the trans swap? If the car ran fine on the stock ECU after the swap, the EJ20G shouldn't matter, as long as the EJ20G-specific wiring is addressed.
TD
Turbo Subies:
'87 GL-10 Turbo 4WD Wagon (pre-Loyale) - SOLD
'90 BJ, EJ22T/DOHC and 5-speed swap - SOLD
'04 FXT, Forged internals, VF39, STI TMIC, Cobb AP- SOLD
'93 Legacy SS - 5-speed, SOLD :-(
'02 WRX GG-SOLD
'96 BD - turbo'd-SOLD

Dynamic Entry
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Re: Adapting an EJ20G ECU

Post by Dynamic Entry » Sun Jul 05, 2015 3:42 am

wtdash wrote: Are there any issues w/your car related to the trans swap? If the car ran fine on the stock ECU after the swap, the EJ20G shouldn't matter, as long as the EJ20G-specific wiring is addressed.
TD
No, the trans swap is complete with no issues.

The thing is that I never really ran it on the stock ECU, it was always piggybacked or otherwise.

The reason I asked is because it seemed like a unique combination of variables that I have that most others don't. Everything is running great, I just didn't want to miss anything.

Thanks!
Andrew

02 WRB WRX
93 White SS "Angel": 4EAT to 5MT 550 Robtune !SOLD!
̶9̶2̶ ̶W̶i̶n̶e̶s̶t̶o̶n̶e̶ ̶S̶S̶ ̶5̶M̶T̶ R.I.P.

wtdash
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Re: Adapting an EJ20G ECU

Post by wtdash » Sun Jul 05, 2015 4:07 am

FWIW, many have done the swap and then upgraded to the Rob Tune/RT...I got there by doing the RT b4 the 5-speed swap, but no issues.

Have fun!
Turbo Subies:
'87 GL-10 Turbo 4WD Wagon (pre-Loyale) - SOLD
'90 BJ, EJ22T/DOHC and 5-speed swap - SOLD
'04 FXT, Forged internals, VF39, STI TMIC, Cobb AP- SOLD
'93 Legacy SS - 5-speed, SOLD :-(
'02 WRX GG-SOLD
'96 BD - turbo'd-SOLD

pabst90-ix
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Re: Adapting an EJ20G ECU

Post by pabst90-ix » Wed Jan 18, 2017 9:32 pm

Ok well this is a serious amateur question, could someone please explain what is meant by merging the pins for the ecu? Cut solder? Seperate from pins then join together. Im slightly confused as i have never done anything like this.

wtdash
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Re: Adapting an EJ20G ECU

Post by wtdash » Thu Jan 19, 2017 6:02 am

Use a Scotch-lock or similar connector ( I like the T-taps).

DE-PIN the B48-5 from the ECU harness plug and connect the wire to the B48-21 w/the T-tap, Scotch-lok, etc.

B48-21 needs to stay connected 'as is' so the ECU can use it.

That help?

Google any 'how tos' if want to see it.

This SVX video is almost identical to the '90-'94 Legacy ECU connectors for a How To on De-Pin:

GL,
TD
Turbo Subies:
'87 GL-10 Turbo 4WD Wagon (pre-Loyale) - SOLD
'90 BJ, EJ22T/DOHC and 5-speed swap - SOLD
'04 FXT, Forged internals, VF39, STI TMIC, Cobb AP- SOLD
'93 Legacy SS - 5-speed, SOLD :-(
'02 WRX GG-SOLD
'96 BD - turbo'd-SOLD

pabst90-ix
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Re: Adapting an EJ20G ECU

Post by pabst90-ix » Thu Jan 19, 2017 2:41 pm

Thats perfext, thanks. I just wanted to make sure i was reading the instructions right. Everything is in place just had to double cbeck.

Huelsdonm
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Re: Adapting an EJ20G ECU

Post by Huelsdonm » Sun Jun 18, 2017 12:08 am

I just got my ej20g ecu and I have two ignitors to wire in, this is a great write up and thanks for the help. I do have a question though; why can't I just merge the trigger pins from the ecu before the ignitor instead of wiring in two ignitors and merging the coil triggers? Does it hurt the ecu to back feed the signal? Will it mess with timing control or dwell? I read this article http://www.rs25.com/forums/f106/t64017- ... h-etc.html (sorry for linking to another site if it is forbidden) and this is exactly what supermoose did. It seems like a very simple solution but I'm sure there are good reasons not to do it this way or it would have been recommended already over here. Maybe I could put a couple diodes in there to avoid ecu damage? If that is the worry? I know rob has spent a lot of time doing developing his methods and I completely trust them, I'm just lazy and looking for shortcuts, hahaha.

Thanks,
Alex

Legacy777
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Re: Adapting an EJ20G ECU

Post by Legacy777 » Mon Jun 26, 2017 5:39 pm

Welcome to the BBS.

I would think if you keep from back feeding signal to the ECU I would think you'd be ok, but it'd probably be good to get some additional feedback. Worst case, you give it a try and let us know. :)
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm

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