NA to Turbo Swap - No Start

[Brunt]

My project is the reverse of what I've found on most of the forum.
Background info can be seen in this build journal...
viewtopic.php?f=25&t=55242

I have the project fully assembled now, but have run into wiring issues.
Hoped it would be as straight forward as swapping the crank and cam pins at the ECU, but should have known better with a project like this.

For now, build photos can be found under Instagram #BruntWorks
https://www.instagram.com/explore/tags/bruntworks/

What I have so far...

Body - '92 Turbo
Engine - '94 NA
Transmission - '94 NA
Crossmember - '94 NA
Rear differential - '92 Turbo (3.9 ratio matches donor vehicle)
Exhaust - '94 NA
Wiring harness (body) - '92 Turbo
Wiring harness (engine) - '94 NA
ECU - '94 NA
TCU - '94 NA

I swapped cam pins (B58.4, B58.5, B58.6) and crank pins (B56.1, B56.2, B56.3) at the ECU.
Also, the ignition fuse under the dash had broken, so it was replaced.

On the first attempt to fire it up, the main relay started buzzing very loudly as soon as I gave the key a half turn.
It cranked and turned over for a brief second; however, I never heard the fuel pump whirring and it quickly stopped sparking.

I discovered SBF No.2 had blown, and after studying wiring diagrams, realized it was due to a difference between the Turbo and NA harnesses, with two pins going to power instead of ground.
I replaced pins F25.13 and F25.16 with pins F27.7 and F27.4 from the Turbo harness's connector to fix the issue.
I also replaced SBF No.2 and the 3 relays under the dash with ones from the donor car.

On the second attempt, the main relay still buzzed a bit, but was WAY more quiet.
The starter no longer cranked.
I could hear the fuel pump running, but oddly, only when the key is half turned.
The main relay continues to buzz quietly, even when the key is turned to off.
Tapping or bumping the relay will get it to stop buzzing.

I am debating three options...
- Keep troubleshooting electrical issues with the existing setup.
- Remove the '94 NA harness from the donor car, hook it up temporarily, try getting the engine running.
- Find someone who really knows what their doing to wrap things up, in the Olympia / Seattle area.

I'm leaning toward option 3
Thoughts?

[dscoobydoo]

Since you have a donor car I would swap harnesses


Sent from my iPhone using Tapatalk

[Brunt]

Thanks dscoobydoo

Was hoping I wouldn't have to pull the dash, but it did come down to that. I swapped the body's harness and got everything hooked back up today. Started right up! Even drove it down the street, everything seemed to work well.

There is a check engine light, but I should have time to troubleshoot that next week.
Code 31 - Throttle Sensor: Abnormal voltage input entered from throttle sensor. (Fail-safe Operation: Sets throttle sensor's voltage output to a fixed value).

Here is a video from today's startup.
https://www.instagram.com/p/BGnKvWhCy9D ... bruntworks

[Legacy777]

I would suggest checking the TPS against the FSM and see how the readings compare and if necessary adjust the TPS using the instructions in the 3rd scan.

http://main.experiencetherave.com/subar ... sting1.jpg
http://main.experiencetherave.com/subar ... sting2.jpg
http://main.experiencetherave.com/subar ... sting3.jpg

[Brunt]

The error code ended up being caused by me forgetting to reattached the speedometer cable to the transmission.
It went away as soon as I got it hooked up.
This also got cruise control working, which makes sense considering the importance of that data.

Been driving the wagon around for a couple months now, working great!
Photos Here

[Legacy777]

Did you clear the ECU after you got the speedo hooked up?

[Brunt]

Nope, the check engine light went away on its own.

[Legacy777]

It's a good idea to check and clear the codes after a problem has been fixed so if you have another problem come up in the future you won't then have to guess whether any of the codes were previous codes.