EJ22 Conversion questions

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EJ22 Conversion questions

Post by CJM70 » Tue Apr 15, 2014 11:07 pm

I am currently installing a EJ22 into my 1970 Bug, daily driver. My donor was a front clip off a 1996 Automatic Legacy. Along with the motor, I removed the wiring harness and ECU. I recently picked up a wiring harness diagram to help in my project, but found out the diagram is for a donor car with a manual transmission.

My Questions are:

1. Is there a difference in the wiring harness between a manual and automatic transmission? I do recall removing/disconnecting some wires off the auto transmission.

2. Being this is an OBDII, what are my options about an exhaust set up and the two O2 sensors? I have the original front Y exhaust, but nothing after that (cats, muffler). I live in a state where my vehicle doesn't need to get smogged. I would also like to put as little exhaust restrictions as possible because, 1)most importantly, keep the cost down, 2) my bug is slightly lowered so I would not like to add too much more to the bottom of my car, and 3) I like the sound from the motor.

-Do I need to get two catalytic converters for the O2 sensors?
-Can I use an "O2 simulator sensor/s" with my stock ECU, instead of using a cat/s?

I appreciate your time and help:)

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Re: EJ22 Conversion questions

Post by Buggin_74 » Thu Apr 17, 2014 5:01 am

Cant vouch for the later OBDII but the OBDI like mine auto and manual use the same loom and ECU there is just one pin which is grounded so the ECU knows what trans.

You would want to run the main o2 sensor.
That is one of the best aspects of the subi conversion is how economical they run by monitoring the o2 readings.
without it it will stay in closed loop mode which will shorten engine life and bring fuel economy down.

The 2nd one is only to make sure the cat is working so could be done away with if you put some sort of simulator in.
1974 Germanlook 1303 Suba-Beetle
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Re: EJ22 Conversion questions

Post by Garey » Wed Aug 16, 2017 7:06 am

What do you mean by a simulator,what is it

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Re: EJ22 Conversion questions

Post by 883 » Wed Aug 16, 2017 1:53 pm

Garey wrote:
Wed Aug 16, 2017 7:06 am
What do you mean by a simulator,what is it
http://www.edgextremesports.com/oxygen- ... GsQAvD_BwE (just one quick example)

O2 sensor simulator(eliminator, emulator) produces a waveform similar to what your ecu expects to see.

"Technically" illegal in the US, but readily available and not too pricey.

The newer the the ECU, the less likely it is to work. The newer stuff is much more sensitive and crafty about reading the post cat sensor signals, most emulators can't fake it well enough. With a '96 ECU you would probably be OK.

Damn Buggin_74, haven't seen you around for quite some time.
No plan survives contact with the enemy.

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Re: EJ22 Conversion questions

Post by maurice » Mon Oct 23, 2017 12:37 am

You don't need the second o2 sensor, it won't throw a code without it.

Buggin_74 is correct, you will need to check and see if the at/mt wire should be grounded or not. I will need to check, but it might also be called the neutral safety switch... But I may be wrong.

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