Ej22t Pinout Questions (for ecu swap in ej18)

Project_Legacy · Post by **Project_Legacy** » Wed May 24, 2006 4:57 am

not8player wrote:Just confirmed that the odb1 Honda ecu use the same connectors as the impreza ej18 ecu. Thought I should share this since I haven’t seen it mentioned before on any of the Subaru forums I visit. When I get a change I’ll take some picture and post them.

Thought this was an interesting fact for anyone looking to install a fuel computer and doesn’t want to hack there wiring, you can pickup a Plug & Play Harnesses for a Honda modify it slightly.

EDIT: nm im retarded.

Natoe · Post by **Natoe** » Tue May 30, 2006 5:52 pm

Matt Monson wrote:Just noticed this thread. There is no easy way to do this. You can't just cut off the connectors and replace with Ej22 connectors and make it run. There are emissions related items on the Ej18 that are not used on the Ej22T, and there are some things on the Ej22T that aren't on the Ej18. And of course, you need to add all the wiring for the turbo. Furthermore, the Impreza plugs into the back of the engine through the firewall, and the legacy plugs in over by the battery.

Personally, if I were to do this again, I would pull a complete Ej22T legacy harness into the Impreza and change any connectors on the chassis side that might need to be changed...

sorry i havent posted earlier, im not on this board as much.

what matt said ----> ditto

if i were to do it again i think i would use the 22T harness instead of modifying the 1.8 harness (all the plugs are the same except TPS) but this would allow less splicing on the ECU side if you left it all intact.

benefits of doing it the way i did: the ECU remained on the passenger floor, i left all boost control and MAF connected to the ECU and ran it through the firewall to the boost sensors with plenty of slack, hacking off the 1.8 ECU meant all the wires i needed were right there to splice on the 22T ECU. overall this was more splicing but i think it simplified things.

using a 22T harness the hard part would be getting ECU wires from the 1.8 that you need over to where the legacy ECU is located, but this can be done. ok im going to finish reading this thread now

Natoe · Post by **Natoe** » Tue May 30, 2006 6:04 pm

Matt Monson wrote:Contact BMXpunk. He started on this project and bailed. He sold his harness to NATOE. Now he runs his 1.8l ECU with a PP and an Ej22T swap. He also runs a TD04 and WRX intercooler.

That '95 coupe in my signature will be getting it's Ej25 swap and supercharger in the next 10 days. I too, will be using a PP.

The fact of the matter is you do not need to reinvent the wheel. For years and years, guys ran Ej18's with turbos on them using just a RRFPR, AFC and ITC for EM. Now with the Emanage and PP available, there is ZERO reason to mess aroung with the wiring in doing a swap onto an EJ18 powered car...

hmm, didnt bmxpunk's blow up? granted he was pushing more boost than stock. (btw sorry man!)

even with the way i did this swap, it was very simple and straight forward. the only tricky part was the diode which they already know about. i obviously struggled through my swap since i did it differently than normal but my biggest problem was that my "sensor ground" was only partially grounded.

now that ive done this once, once the harness is plugged into the motor, i could rewire the car in less than a day, however long it takes to splice 40-50 wires. its very straight forward and driveability is amazing.

remember i ran it on the 1.8 ECU for 1000 miles until i got sick of not being able to go part throttle, and am very glad i rewired (if you do you will not want to go back to the 1.8 ECU)

because ive done this wiring, it makes going EJ20G easy since the wiring is already done, which i plan to purchase a motor soon.

Natoe · Post by **Natoe** » Tue May 30, 2006 6:09 pm

Biggest benefit i see for staying on the 1.8 ECU is the fact that it is less restrictive for making power... with an Emanage or PP im sure you can tune out a lot of the fueling/hesitation issues, but stock EM has a MAP sensor already and knows how to fuel for boost.

Project_Legacy · Post by **Project_Legacy** » Tue May 30, 2006 6:26 pm

wow, i never thought about the map sensor. what would i do for the map sensor on the 1.8 ECU? i have the ej22t map sensor, but now that you just brought this up, how will i even use it?

Natoe · Post by **Natoe** » Tue May 30, 2006 6:28 pm

you cant, im just pointing out that the turbo ECU uses the MAP, wastegate solenoid, pressure exchange solenoid, to fuel for boost while the NA ecu doesnt know there is boost, just that its flowing a lot of air.

Project_Legacy · Post by **Project_Legacy** » Tue May 30, 2006 7:10 pm

are you for real?? i dont use any of the strut tower sensors at all for the 1.8 ecu? damn, i just bought those too! i seriously dont know what i was thinkin when i did...

so Natoe, when you used the 1.8 ECU, what did you use to control fuel/timing/boost?

Natoe · Post by **Natoe** » Tue May 30, 2006 7:38 pm

i didnt use anything to control fuel or timing which is why it was so bad, but even with some control bmxpunk never got rid of all of the hesitation (give it throttle at low rpm and it bucks)

there is no use for the sensors on an NA ECU... though all you need is an ECU and the boost control part of the wiring harness and you have everything i did to do the wiring swap (assuming you have the right MAF)

Project_Legacy · Post by **Project_Legacy** » Tue May 30, 2006 7:44 pm

Natoe wrote: though all you need is an ECU and the boost control part of the wiring harness and you have everything i did to do the wiring swap (assuming you have the right MAF)

when you say ecu here, are you talking about the ej22t ecu, or the ej18? i do have an MAF, not sure if its still working correctly, but it should. would i be able to use the metal housing MAF like plug & play? or should i just use the N/A one and see what i can do with that? were you running the metal housing MAF?

Natoe · Post by **Natoe** » Tue May 30, 2006 7:48 pm

if you still plan on using your EJ18 ECU, you have to use the plastic MAF and all the EJ18 sensors.

what i meant is you just need a turbo ECU and some plugs and you can rewire. im not sure if you have any intention of doing so or not but you dont need much in order to be able to.

my3awds · Post by **my3awds** » Tue May 30, 2006 9:37 pm

It's too bad you didn't document your rewire, Natoe. Not8player and I have been trying to figure out 9 or so wires on the ej22t ecu plug side and how they wire into the ej18 harness side. Gave up on it since it's more trouble then it's worth trying to figure it out. Not that big of a deal anyway since I'm going piggy back, but it would still provide useful for those that might want to stick to factory stuff without the need of a complete harness swap.

Speaking of MAF's, has anyone rewired a jdm wrx/sti MAF to their car for more air? We've done this in the dsm world with MAF's from newer generation eclilpses to the older.

Natoe · Post by **Natoe** » Tue May 30, 2006 10:36 pm

i could document it.... all the key info are in my threads somewhere here and on nasioc. only thing i didnt document is the matching up of wires, stuff like VSS, all the sensors, grounds, ignition, its all very straight forward. looking at both ecu pinouts they all match up perfectly except for things that have been covered. any problems you do run into you can ask on here or pm me like you have on nasioc and ill do my best to help.

Project_Legacy · Post by **Project_Legacy** » Wed May 31, 2006 9:38 am

i will be buying an emanage tomorrow, so i have a question.

is there a way to use the ej22t map sensor (if i need to, or not) with the emanage? i know they have a seperate 3 bar map sensor and harness you can purchase, but was wondering if this was another solution i could use.

let me know what you guys think!

Post by **Legacy777** » Wed May 31, 2006 6:28 pm

You use the MAF sensor signal to control fuel.

Natoe · Post by **Natoe** » Wed May 31, 2006 8:25 pm

and you cant use the legacy MAP sensor i dont think, usually use a GM map

Project_Legacy · Post by **Project_Legacy** » Wed May 31, 2006 8:41 pm

oic... basically, i can choose to buy a MAP sensor and put it on, and tune boost with that, or i can just use the stock MAF sensor, is that correct?

i joined a yahoo emanage group, and they say you can switch MAF sensors with equivelant (i.e. hotwire type with another hotwire type). but anyway, werent we discussing before, that the plastic MAF's had a wider range than the metal ones?

Post by **Legacy777** » Fri Jun 02, 2006 2:58 am

Project_Legacy wrote:oic... basically, i can choose to buy a MAP sensor and put it on, and tune boost with that, or i can just use the stock MAF sensor, is that correct?

i joined a yahoo emanage group, and they say you can switch MAF sensors with equivelant (i.e. hotwire type with another hotwire type). but anyway, werent we discussing before, that the plastic MAF's had a wider range than the metal ones?

Not sure I understand your question. You can not alter the fueling of the car by adjusting the MAP sensor signal, new or legacy MAP sensor.

Project_Legacy · Post by **Project_Legacy** » Fri Jun 02, 2006 6:21 am

really? o, i thought you could. what do people mean when they say "i like to tune using MAP instead of MAF" then?

Post by **Legacy777** » Fri Jun 02, 2006 6:56 pm

Project_Legacy wrote:really? o, i thought you could. what do people mean when they say "i like to tune using MAP instead of MAF" then?

They're using a different computer then the stock ECU.

The stock computer wants to see a MAF sensor. So even if you were to setup a piggyback to use the signal from the MAP to tune, it wouldn't do squat because the stock ECU adjusts fuel based on the MAF sensor......and you couldn't use a MAP sensor to send a signal back to the stock ECU as a MAF signal because the response curve of the two sensors are completely different.

Project_Legacy · Post by **Project_Legacy** » Sat Jun 03, 2006 2:50 am

oo... i see what you mean now. thanks for clearing that up! so, basically there is no way to use a map sensor for the 1.8 ECU then. i just needed to clear that up before i go and buy one. hehe

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Ej22t Pinout Questions (for ecu swap in ej18)