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EJ22 swap, ODB-I vs OBD-II


Dj7291993
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So, I'm hoping to do the EJ22 swap in my 87 GL Coupe over the summer (as long as I can get the funds), and was wondering what the pros and cons were to using an OBD-I engine/harness vs and OBD-II. I've been reading numbchux's guide for it, and it seems easy enough. I should probably note that electrical is one of my strong points, in fact, I'm probably most confident in the wiring for the swap. Now, I know it's possible to use an OBD-II engine for the swap, but the guide only covers OBD-I. So, what are pros/cons, how much harder would it be, and is there anything else I should know?

 

Also, I haven't found a car yet, but if I happen to find a good deal on a later car ('95+), then I'd like to know if I can/should get it. More than likely, I'll end up with an earlier one, and this won't be an issue, but hey, better safe than sorry.

 

P.s. I did use the search bar, to no avail, and I don't presently have time to dig through all the results to find what I'm looking for.

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The OBD-II harness is separate from the body harness whereas the OBD-I is integrated with the body harness. OBD-II is also more flexible with changes such as cams and headers.

I'm running OBD-I in mine, it seems work alright, but my next EJ swap will be OBD-II.

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Pros and cons to each.

 

I have an EJ swapped car with each.

 

My lifted wagon is OBD-I.

 

PROS) Easy to get whole parts cars cheap, dual port engine opens up header options, and no rev limiting built into ECU.

 

CONS) The only downside I see with it is that stripping the harness is a little more "cluster F****D" with the big SMJ and some akward harness routing. Also, no real scanner compatible live data (unless you happen to have an old "select monitor" from a dealer.

 

My Street car is OBD-II

 

PROS) Easier harness strip, no SMJ, engines have a bit more torque and roller rockers, and if you leave the OBD-II port, hooks up to any scanner and stream data. donor cars (and parts) are newer.

 

CONS) Rev limited to 6k. Pickier in limp mode (if VSS code set, rev limited to 4k) Throws more CELs for Fuel temp sensor, Fuel pressure sensor(these don't seem to affect driving). donor cars are newer/higher cost

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I've done quite a few of each. Stripped probably a dozen or more of each style and personally installed or worked on at least half of those. I can strip either harness while watching TV and drinking beer :drunk:

 

OBD-II all the way for me.

 

The Fuel temp sensor and Fuel pressure sensor aren't a problem for 95 and 96 (except CA cars) as they don't have them.

 

Actually I recently had the pleasure of stripping a '95 OBD-II 5 speed harness and of all the ones I've ever done I liked it the best. Finding the diagrams for it wasn't hard (have them in digital form if anyone needs them) and it had a much less messy harness. I would love to find more of these :-p.

 

GD

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The Fuel temp sensor and Fuel pressure sensor aren't a problem for 95 and 96 (except CA cars) as they don't have them.

 

 

Uh....yeah they do.

 

My donor was a 96 Outback w/EJ22 and 5mt. NOT a California car.

 

Do your OBD-II cars throw any CEL?

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Uh....yeah they do.

 

My donor was a 96 Outback w/EJ22 and 5mt. NOT a California car.

 

Do your OBD-II cars throw any CEL?

 

I remember a '96 Legacy that I had to replace the fuel pump pickup tube on and I got a pump assembly from the JY from another '96 thinking they would be identical - the one I was working on had the temp sensor and the one I got from the yard didn't. I swapped the sensor over and all was good.

 

When I strip harnesses I account for every single wire and I can say that in most of them I've done there has been no fuel temp or pressure. I just did that 95 like a couple weeks ago and there's no wires for those on the ECU connector.

 

I would conjecture that this may have been a mid-year adjustment in 96 sometime. Some have it but most don't seem to.

 

97+ definitely do have them. I've stripped enough of those harnesses to say that for sure.

 

GD

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I've done quite a few of each. Stripped probably a dozen or more of each style and personally installed or worked on at least half of those. I can strip either harness while watching TV and drinking beer :drunk:

 

OBD-II all the way for me.

 

The Fuel temp sensor and Fuel pressure sensor aren't a problem for 95 and 96 (except CA cars) as they don't have them.

 

Actually I recently had the pleasure of stripping a '95 OBD-II 5 speed harness and of all the ones I've ever done I liked it the best. Finding the diagrams for it wasn't hard (have them in digital form if anyone needs them) and it had a much less messy harness. I would love to find more of these :-p.

 

GD

 

I'm doing an ea to ej swap using a 98 legacy 2.2 5spd awd. I don't know how much of a difference there is in the wiring diagram, but I'm a visual learner so any pictures/diagrams would help. Especially pics/diagrams of simplified harness. I've swapped an ea81 with 4spd d/r out and into this brat but this is my first time with an "upgrade" I plan to use as much as I can off the legacy, so any advice is welcome and appreciated!

Thanks

Mike

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I'm doing an ea to ej swap using a 98 legacy 2.2 5spd awd. I don't know how much of a difference there is in the wiring diagram, but I'm a visual learner so any pictures/diagrams would help. Especially pics/diagrams of simplified harness.... so any advice is welcome and appreciated!

Thanks

Mike

 

I don't have any pictures, but here's some links that will be helpful:

 

http://www.northursalia.com/modifications/misc/wiring/wiring.html

 

http://wordpress.suberdave.com/?page_id=175

(password: Subaru)

 

http://www.numbchuxconversions.com/downloads.htm

 

GD

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hmm.....

 

I'm using a 93 Legacy computer with an EJ18 in my 84 wheeler.

 

I don't think I've ever hit fuel cut????

 

I suppose I ussually do shift by 6500.......since the redline on the EA81 tach is 5500......Makes it feel like it's really revved out.......in my head at least.

 

I do hit the rev limiter (6k) in my 86 wagon. Tach shows 6500 redline......but fuel cuts before that:banghead:

 

Guess it just takes getting used to.

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