crevasse

I've been slowly working on a 1UZ swap in my 2nd gen 4Runner (1995), and it is very close to being finished. The engine and trans are in, driveshafts are connected, fuel lines are connected, and all of the wiring in the engine bay is done. The final thing I'm hung up on is connecting the original 3VZ body harness (IH1 plug) to the Lexus ECU "4th plug" (E12 on a '94 LS400) and the IL1 and IL2 (body) plugs. Every guide I have found here or Lextreme or any other Toyota forum has only had specific wiring instructions for 90-92 LS400 motors, which have different wiring than 93-94.

Sanctfy has a great post here on this forum (https://www.yotatech.com/forums/f161...0f-4x4-292244/) where he covers which wires he needed to splice together, but his 1UZ was from a 92 LS400 so only some of it is relevant for me:

I have a physical copy of a 94 LS400 factory service wiring manual, so my issue isn't tracing wires and identifying pins; I have all of that mapped out. Some of the splicing I already figured out on my own by studying the service manual. For example, I already identified and spliced together BATT, starter, MREL, CEL, tach, and +B.

My issue is not knowing how to deal with the fact that in the 94 LS400 there doesn't seem to be a circuit opening relay for the fuel pump to turn on.

Am I just blind and is there already a write up out there somewhere that clears up how to wire in a '94 LS400 1UZ on a 2nd gen? Or, could someone point me in the right direction for getting the IGSW and FPR wired correctly?

picture of my sort-of-close-to-complete engine bay:

Numbchux

The 1UZs use a fuel pump controller to vary the voltage to the pump as it's needed, instead of a relay.

Many people bypass this and just wire a relay triggered by the ignition switch. I do not think this is acceptable, as in the event of an accident, the fuel pump will continue to run. My engine did not come with one, but I bought a used controller with pigtail on ebay and wired it in.

crevasse

Thanks for the reply. That's the little module that's in the trunk of the LS400, correct? I'll track one down and figure out how to wire it in...anything tricky that I need to watch out for when wiring that in?

Rowanholland

Hey there, I have a 2nd with a 3.slow 5sp manual with no issues but every time I’m driving 75 and the rpms are at 3000 I wish I could just grab one more gear. I know the 2006 tundras with the 1grfe came with a 6sp manual. Does anyone know how hard it would be to swap one in? Has anyone done it? I know I would probably need a new drive shaft and I’m guessing some kind of adapter plate for the trans to the 3.slow I would love to hear your thoughts!!
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Numbchux

I assume so. I never pulled it from the donor car, but they're generally in the trunk on other cars. Here's what the one that was correct for my SC400 donor looks like:



It was super easy to copy the factory wiring to it. Off the top of my head, power, ground, signal from the ECU, and power out to the fuel pump (I'm pretty sure the pump was still chassis grounded).

Welcome. I'm glad your searching, but you'll probably have better luck starting a new thread with this question, you'll get more responses.

I did a little research into the 1GR 6-speed, as I'm building a 2GR car. The 1GR has a different bellhousing bolt pattern than the older V6s. And the 6-speed (RA61, IIRC) does not have a separate bellhousing like the R series. Also, does not have a good reputation for longevity.

It is possible to swap out the 5th gear in your R150 for a taller one. Google up on that. That's probably the direction I'm going with the 2GR build.

crevasse

Did you need the giant resistor relay? This thing here: https://www.ebay.com/itm/22422033366...evt=1&mkcid=28

Numbchux

No. 94 uses the fuel pump controller, earlier models (I just checked 92 and 94) use a relay and a resistor, (relay switches between full and partial voltage, controller can infinitely vary).