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1991 EJ22NA to VW BUG - ECU Questions.

Featured Replies

Hello all,

 

I've been reading your site and am grateful for all the useful information

 

I am in the middle of a EJ22na to VW bug engine swap.

 

I have a donor car. 1991 Legacy (mfg 11/90)

 

673041.jpg.

 

A few questions...

 

1. The wiring diagram for clutch switch lists connector b58 pin 9. My ECU does not have a wire here??? Any thoughts?

 

2. Also, to clarify. To select Manual Trans mode, do I ground pin 20 on b48? or do I leave it open? Service Manual says "5 volts" for manual trans with ignition on. Zero for AT.

 

 

Thanks. I may have more questions.

1. The wiring diagram for clutch switch lists connector b58 pin 9. My ECU does not have a wire here??? Any thoughts?

 

Guessing your donor car was an Automatic? You wont have a wire in the harness between the ECU and the SMJ

 

2. Also, to clarify. To select Manual Trans mode, do I ground pin 20 on b48? or do I leave it open? Service Manual says "5 volts" for manual trans with ignition on. Zero for AT.

 

 

Leave it ungrounded. The volts will be 5v if measured. If you ground it the voltage is driven low and if measured would read zero.
  • Author

Thanks. It's good to see others crazy enough to attemp such feats.

 

One more question if you don't mind...

 

It did come out of a MT car (?), but who knows what's happened with that car in the last 20 years. Should I put a pin 9 in? Or simply run without a clutch switch? Will I see any benefit from running a clutch switch? It would seem that the donor didn't have any error codes...

 

But, If this was an AT car, do I need to scavenge the AT control module to complete the swap? I did read something to that effect in my hours of searching.

 

I will be installing a neutral switch, if that helps any.

 

Thanks ahead of time. I am excited to put the final coat of shirink wrap on this weekend.

For that year engine it's ODB1, and for ODB1 cars the the only communication between the ECU and the TCU is for engine RPM, and that's coming from the ECU going to the TCU, so it doesn't effect the ECU at all, so you do not need the TCU to complete your swap.

 

Sounds like a fun project, keep up the good work!

  • 3 weeks later...
  • Author

Well,

 

I test started it today.

 

It won't idle, like it's missing a cylinder.

 

The ECU is giving me a code 22, knock sensor.

 

Even when I clear codes, it gives me this error before running again.

 

Funny, but this is one of the few sensors I didn't mess with the wiring.

 

I did check continuity between knock sensor and block, none. (like it's supposed to be).

 

Are these symptoms consistent with knock sensor failure??

 

Any thoughts??? I hope I didn't screw anything else up, like injector wiring or something to miss a cylinder.

If something isn't right like a vacuum leak, or a PCV hose missing, the ECU can determine that it's unable to control the idle within normal. Ussually a leak or an IAC issue.

 

When it deems this has happened, it cut's fuel to the #1 injector as a way of keeping the idle from running away.

 

Really sucks.

 

So you need to figure out what's up with that.

 

Check the idle switch in the TPS is closing, check the IAC is hooked to the intake boot, MAF clamp tight, no vac leaks, throttle cable not too tight.

 

Solve the idle, and the misfire will likely disappear.

 

Knock sensor code won't give any running problems. Just needs a new one if it faults right off.

  • Author

Very good, Thanks for the info.

 

Clean contacts, checked harness continuity of Knock sensor, checked output voltage of ECU pin -- all good.

 

checked resistance of knowck sensor - service manual says 560 k ohm, but when I check I get an increasing number starting at approx 550 k ohm and will continue to climb to 800 k ohm or better if I leave my meter on there????

 

I will go through the manifold now. I hope there is a gaping hole that I can plug - please please please....

  • Author

YYYYYYIIIIIIIIPPPPPPPEEEEEEE!!!!!

 

:banana::lol::grin::slobber::rolleyes::eek:

 

Stupid me. I was redesigning the intake and for a while I was thinking of using a cone intake, but when I went back to the air box I left a rubber coupling connected and figured it would keep debris out while I modified it.

 

Anyway, that coupler wasn't letting very much air in.

 

Thanks for pointing me to the intake. I runs perfect now, for the few seconds I did run it (no coolant). It would go to idle fine and come off idle fine.

 

SWEET!! (Can you tell I'm excited)

 

Thanks for all the information on this forum.

 

One more dancing bannana for good cheer :banana:

  • Author

Pictures... Good plan.

 

Here is my "build page" from another site. I didn't start with Subaru in mind, the idea evolved slowly. I bought the subaru around page 4.

 

build page

 

Here is a VERY short u-tube video of it running.

 

 

I still have a lot of work to do to make it drivable, but now that it's running I have lots more ambition.

Edited by ts39136

  • 4 months later...
  • Author

 

Finally got around to taking a video, not the best, but I'm super excited to get this thing out and play!

 

I had a problem with one of the engine connectors and had to bypass a fuel injection wire around the plug (corroded plug), but otherwise been purring like a kitten! Sounds good with the glasspacks on there.

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