I need help with my engine swap!!!

csdream

New Member
Feb 24, 2006
8
0
0
Hood River, OR
Hey everybody. I have an 86.5 which i burned the motor up first week i had it. It'd been sitting for two years when i bought it so it wasn't a big surprise. i threw in a jdm replacement, but it ended up being an 89-92 motor. i've got a 90 ecu in place, and an 89 harness . the harness doesn't plug into two red vaccuum plugs underneath the intake manifold and has an extra white clip that doesnt go to anything. when i hook the battery up, my fuel pump resistor buzzes nonstop and my temp guage flys all the way up to overheated. it seems my power is reversed, but i changed nothing about the engine bay, except for the engine/harness. does anybody have any clue if i'm missing something for the swap, or if i fcked up somewhere? please people, i need help.....:aigo:
 

csdream

New Member
Feb 24, 2006
8
0
0
Hood River, OR
tried that to begin with, obviously with the old ecu too, and something reads wrong. i swapped the injectors/distributor and the engine must have not liked the readings at the computer end, because that's when the buzzing started. 89 harness doesn't work with 86 ecu of course, so i got the 90 and that didn't change anything.
 

supra90turbo

shaeff is FTMFW!
Mar 30, 2005
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Start over.
Get matching year harnesses. Get an 86.5 ecu and harness. Related sensors, and so on.

There's a big wiring change in mid-89. You're much better off going with anything 88 and down.
You'll need an ECU with yellow connectors, and also a harness with yellow plugs.

Dr.J is the man here. You're gonna have to find out what the wiring problem is before you do anything else
 

csdream

New Member
Feb 24, 2006
8
0
0
Hood River, OR
well, pretty sure the 89 harness was crap, not sure why...but the 86 sensors, including the two on the thermostat housing and the connection for the distributor don't seem to work at all on the new motor, with either ecu. any idea why i don't have the connections on the harness for the vacuum lines on the driver side of the engine? bad harness maybe??
 

csdream

New Member
Feb 24, 2006
8
0
0
Hood River, OR
are you guys sure the 86.5 harness/ecu/sensors will work on an 89-92 motor. absolutely positive???? if so, the only problem i should have is splicing the harness to the distributor, since it changed. unless of course i put an 86.5 distributor on it, but i don't know that i want to do that....unless i have to
 

supra90turbo

shaeff is FTMFW!
Mar 30, 2005
6,152
32
48
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No, what we're saying is that it won't work.
I mean, it WOULD, but that's too much work required when you can just get an 86.5 harness, ecu, and sensors.

You're trying waaaay too hard to make this work. Get it back to 86.5 parts.
 

csdream

New Member
Feb 24, 2006
8
0
0
Hood River, OR
well, i still have the 86.5 harness and ecu, but i'll need new sensors cuz the others were old and broke in the swap. got rid of the old motor anyway. but these pieces will work with the new motor???? one thing i don't understand is that with both an 86.5 and 90 temp guage sensor, my guage still flies off the chart. and that's only when i hook up the battery. when i turn the key the guage goes back down, but that's still sign of energy traveling backwards. i don't understand why my fuel pump resistor buzzes though. maybe i have an extra ground that is reversing all energy??? i don't know; what's your opinion on that?