How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

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James614
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by James614 »

Rob designed the tune for the EJ20G and its thoroughly tested on his personal EJ20G powered car. That we can use the 20G ECU on a 22T is just a bonus for us.

Somewhere Rob mentions running his code on an NA ECU, and it ran in batch fire injection mode. That was a while ago, no idea if he ever looked into it further.
93 Touring Wagon (EJ20G 5spd Swap) -- Finally back and running strong as ever!

05 Outback 2.5XT 5spd -- Now the wife can have her SUV and get in on the turbo Legacy goodness at the same time.
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 »

Rob has one of my 92 non-turbo JECS ECU's. He was doing some testing to see if they could be used as base platforms for the Robtune vs. the EJ20G ECU's. I'm not sure what he's found and if it would work or not.
Josh

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1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by SILINC3R »

Just realized both sets I have didn't come with the bolts to attach it to the head. Anyone got an idea of what size bolt to use.
Tony
90 LS Spec rio red sold
91 SS rio red R.I.P
90 Mazda Miata
2005 GT SWP
92ss satinsvoice wrote:LOL! that block was like F*** THIS! IM OUT!
mike-tracy wrote:Word. I'd love to get my hands on one of those trannies, but I just can't stomach the cost
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by SILINC3R »

Also I wasn't able to get pigtails with mine so I don't know which is the power, signal and ground pin.
Tony
90 LS Spec rio red sold
91 SS rio red R.I.P
90 Mazda Miata
2005 GT SWP
92ss satinsvoice wrote:LOL! that block was like F*** THIS! IM OUT!
mike-tracy wrote:Word. I'd love to get my hands on one of those trannies, but I just can't stomach the cost
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by cj91legss »

There's a writeup on Nasioc about converting from the old style cop to the new style cop. That'll have the answer to the plug info. As far as the bolt, I think kimo or myself can measure it for ya. I'll be home in a little bit.
Last edited by cj91legss on Sat Nov 15, 2014 1:11 am, edited 1 time in total.
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by SILINC3R »

Found it thanks

Pin1- Pin2- Pin3-
12v GND Signal

Inboard Outbard
Tony
90 LS Spec rio red sold
91 SS rio red R.I.P
90 Mazda Miata
2005 GT SWP
92ss satinsvoice wrote:LOL! that block was like F*** THIS! IM OUT!
mike-tracy wrote:Word. I'd love to get my hands on one of those trannies, but I just can't stomach the cost
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by cj91legss »

12mm bolt and it's 1-1/4" long.

It's only threaded for half the bolt.
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by SILINC3R »

Alright so just got done with the instal last night including Robtune. Car was starting finally got it to start by unplugging the MAF. Read that somewhere to unplugg it and it worked. However it is running on 2 cylinders, 2&4. Injectors are good all around. Double checked by unplugging on bad side with no change and on good side which stalled the engine. Switched out coils and swapped working one from 2 to 3 with no change. Checked Spark plugs on 1&3 and are brand new. I have power and ground to the coils so I guess it has to be the signal. Wondering what the best way to confirm is.
Tony
90 LS Spec rio red sold
91 SS rio red R.I.P
90 Mazda Miata
2005 GT SWP
92ss satinsvoice wrote:LOL! that block was like F*** THIS! IM OUT!
mike-tracy wrote:Word. I'd love to get my hands on one of those trannies, but I just can't stomach the cost
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by SILINC3R »

So put in another ECU with no change. I have checked for signal voltage at the ECU and at the coil plug and checks out. Getting ground at coil plug as well as 12V power. Checked for spark but not getting spark on bad side. Getting spark on good side.

Kimo and I have done pretty much everything check and test with the issue not being resolved. Anyone have any other thoughts.
Tony
90 LS Spec rio red sold
91 SS rio red R.I.P
90 Mazda Miata
2005 GT SWP
92ss satinsvoice wrote:LOL! that block was like F*** THIS! IM OUT!
mike-tracy wrote:Word. I'd love to get my hands on one of those trannies, but I just can't stomach the cost
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by SILINC3R »

Reposting this

writing on here incase anyone has some insight. I have spent over 7 hours reading across the far reaches of the internet and through many old threads in many a forum. Everytime I seem to be close to a resolution no more post are writen and the thread is lefting hanging as if the problem has driven the OP insane or worse deceased.

Car runs on cylinders 2&4. Most threads are of no spark at all or only one cylinder having an issue. I have installed a EJ20 ECU and gone COP. What is weird is the 2 signals that are added to the ECU work but the 2 already present are not sparking.

I have done the following:
tested for power, ground and signal at the COP plug--good
tested for signal at the ECU--good
tested for spark by holding spark plug to ground--no go on bad side/good on good side
swap COP from good side to bad side--no change
swapped in a known good robtune ECU--no change
checked length of offending signal wires for breaks--good
listened to fuel injectors with screw driver--good

I am at a loss. If someone can find the answer I will paypal you 10 bucks.
Tony
90 LS Spec rio red sold
91 SS rio red R.I.P
90 Mazda Miata
2005 GT SWP
92ss satinsvoice wrote:LOL! that block was like F*** THIS! IM OUT!
mike-tracy wrote:Word. I'd love to get my hands on one of those trannies, but I just can't stomach the cost
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 »

Tony,

To recap, I'm going to state some things and ask questions, please confirm or clarify them.

You are using an ej22t engine meant for the wasted spark setup. With that engine you have tested both a stock EJ20G ECU & Robtune ECU meant for the turbo Legacy.

Where are you sourcing your 12v power and ground for the coil packs?

Did you run new wires from the ECU's ignition outputs directly to the GD COP? Or did you use any part of the factory wiring harness?

Was the engine running fine with the stock ej22t & wasted spark coil before you decided to run the EJ20G ECU & convert to the COP setup?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by SILINC3R »

Legacy777 wrote:Tony,

To recap, I'm going to state some things and ask questions, please confirm or clarify them.

You are using an ej22t engine meant for the wasted spark setup. With that engine you have tested both a stock EJ20G ECU & Robtune ECU meant for the turbo Legacy.

Where are you sourcing your 12v power and ground for the coil packs?

Did you run new wires from the ECU's ignition outputs directly to the GD COP? Or did you use any part of the factory wiring harness?

Was the engine running fine with the stock ej22t & wasted spark coil before you decided to run the EJ20G ECU & convert to the COP setup?
I am using a EJ20 engine that was running a EJ22T ECU with wasted spark.

I am sourcing my 12V power from the stock EJ22 coil pack plug.

Ran new wires to the EJ20 ECU pins 7, 8, 9, 10 to the GD COPs.

and yes the engine was running fine before I swapped in the ECU and switched to COP.

Thanks for the response. Hopefully that helps you out more.
Tony
90 LS Spec rio red sold
91 SS rio red R.I.P
90 Mazda Miata
2005 GT SWP
92ss satinsvoice wrote:LOL! that block was like F*** THIS! IM OUT!
mike-tracy wrote:Word. I'd love to get my hands on one of those trannies, but I just can't stomach the cost
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 »

What about the ground wire?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by SILINC3R »

Legacy777 wrote:What about the ground wire?
uh I have ground wires haha. Not sure what you mean Josh
Tony
90 LS Spec rio red sold
91 SS rio red R.I.P
90 Mazda Miata
2005 GT SWP
92ss satinsvoice wrote:LOL! that block was like F*** THIS! IM OUT!
mike-tracy wrote:Word. I'd love to get my hands on one of those trannies, but I just can't stomach the cost
Legacy777
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 »

Where did you physically locate the ground wire that is going to the coils? Is it tied into an existing ground or did you bolt it to a spot on the engine?

I looked at a previous thread and it looks like you grounded the coils on a bolt that screws into the valve cover, is that correct? If so, I would recommend moving it to some place on the engine block or intake manifold.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
cj91legss
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by cj91legss »

The ground he chose should actually ground to the head.
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by James614 »

Rob recommends grounding them to the bolt that holds the coils in the cylinder head in his write-up, which is how I did it. The OEM WRX harness does have them grounded to the common point in the engine's wiring harness if I recall correctly. But when installed properly there's 0 ohms between those mounting bolts and the main ground bolt on the intake manifold (assuming there's a clean connection on all the bolts of course).
93 Touring Wagon (EJ20G 5spd Swap) -- Finally back and running strong as ever!

05 Outback 2.5XT 5spd -- Now the wife can have her SUV and get in on the turbo Legacy goodness at the same time.
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by SILINC3R »

Welll gentlemen, it was the ground!!! Moved it to the block and then ran another ground to the chasis. I also was using the wrong mutlimeter and was getting bad readings, switched to the good one and could see the issue. Thanks for all the help, you guys are awesome.

So who do I owe?!

Image
Tony
90 LS Spec rio red sold
91 SS rio red R.I.P
90 Mazda Miata
2005 GT SWP
92ss satinsvoice wrote:LOL! that block was like F*** THIS! IM OUT!
mike-tracy wrote:Word. I'd love to get my hands on one of those trannies, but I just can't stomach the cost
cj91legss
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by cj91legss »

Who ever you talked to the most!

I got proof I told you to move the ground on facebook.

91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by mike-tracy »

I got proof over text ;)
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote: Mon Jan 14, 2002 10:23 am Wait....I'm confused now.
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by cj91legss »

Ro-sham-bo you for it mike. I go first...
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 »

Glad you got it working Tony!! :)
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by SILINC3R »

Again thanks for the great write-up Kimo

Make sure your ground isn't on the valve covers. If you have singal voltage and 12v power and it still ISN"T sparking than it IS a grounding issue.

And looks like I have to split it 5 ways haha, feel free to send me your paypal to collect your 2 dollars!
Tony
90 LS Spec rio red sold
91 SS rio red R.I.P
90 Mazda Miata
2005 GT SWP
92ss satinsvoice wrote:LOL! that block was like F*** THIS! IM OUT!
mike-tracy wrote:Word. I'd love to get my hands on one of those trannies, but I just can't stomach the cost
James614
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by James614 »

Wait, did you have it grounded to the valve cover itself and not the mounting bolts for the coil packs?
93 Touring Wagon (EJ20G 5spd Swap) -- Finally back and running strong as ever!

05 Outback 2.5XT 5spd -- Now the wife can have her SUV and get in on the turbo Legacy goodness at the same time.
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 »

James614 wrote:Wait, did you have it grounded to the valve cover itself and not the mounting bolts for the coil packs?
Yes he did. These are pics from his build thread.

Image
Image

Repositioned ground with added chasis ground.

Image
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

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