96 4Runner Motor & Manual Trans Swap

Mbanks

New member
Well where to start off, I guess Thank you guys for all of the information. I spent many nights lately reading up on doing this swap from a 98 4runner 3.4 W/ Manual Transmission into a 96 that had the same motor but with a automatic transmission.

The reason for the swap was, the 98 was from up nothing. The frame was literally falling apart, the rear struts weren't attached to anything, the rocker panels were completely gone(almost). And I had purchased a 96 4Runner that supposedly had a blown motor. Well come to find out, it was the flex plate had broken apart & the guy just didnt know what he was doing.

So my smartself decided what better to do that to swap my motor and transmission into the 96.

To start the swap off, I took everything out that I thought i needed from the 98. Motor, trans, Full Engine wiring harness, ECU, driveshafts ETC.


After reading everything, i figured it was pretty straight forward. Swap everything over and all will go smooth.


Well tonight after getting everything in I hit a speed bump. I didnt think about what to do when the truck thought it was still in park. Now, i had assumed that since swapping over the 98 ECU that everything would work properly. But obviously after swapping everything it didnt. I can start the car by manually putting power to the starter. It runs & drives fine. Just the reverse lights do not work & the truck will not start with the ignition.


I have read what to do if you are using the wiring harness from the automatic transmission from jumping wires from the main transmission plug.

But my question is, What to do if I'm using the wiring harness from the manual transmission..... I am kind of at a stand still.


I know, I am the guy who is asking a question. But out of an entire motor and transmission swap, after reading for hours and hours on end of other people doing swaps. I finally had to ask a question.
 
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I'm no expert, but I know there are a bunch of wiring differences between 96 and 98. I would have sourced a 1996 M/T ECU if I did that swap.
 
You need to find the park/neutral switch wire and ground it, or better yet run it over to the clutch start switch. If you replaced the engine wiring but not the dash wiring, the wiring for the auto and manual are different in the dash wiring. The starter relay runs to the clutch switch in the manual and the park/neutral switch in the auto. In my 97 the park/neutral wire was in the two separate plugs that do not go into the ECU,it was the smaller of the black/red wires. Best to find a wiring diagram if you cannot find it. Took me a whole day to figure out that piece of the puzzle, it was worth it when she fired up
 
You need to find the park/neutral switch wire and ground it, or better yet run it over to the clutch start switch. If you replaced the engine wiring but not the dash wiring, the wiring for the auto and manual are different in the dash wiring. The starter relay runs to the clutch switch in the manual and the park/neutral switch in the auto. In my 97 the park/neutral wire was in the two separate plugs that do not go into the ECU,it was the smaller of the black/red wires. Best to find a wiring diagram if you cannot find it. Took me a whole day to figure out that piece of the puzzle, it was worth it when she fired up

Great first post. Welcome to the forum! You probably can fix this by repinning a few wires on those non-ECU plugs he referred to to avoid diving deep into the wiring. You will really need the EWD's for '96 and '98 to figure it out. $15 on TIS for a day-pass and you can download them all. If you have them, I can point you to what to do fix those issues without it taking a day. But I need the EWDs. Unfortunately, the only EWDs I have are '99 and '02. No help in your case. Good job getting it done with just those issues. It's never an easy job.

Did you move the Clutch Start Cancel switch over?

EDIT: Hold the presses, look what I found,(This is the '98.)
 

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I also found the '96. But the site won't let me upload it--no idea why. But, if you go into the left kick panel on the '96, find the IG1 plug joining the engine room wire to the cowl wire, there should be a black/red wire at Pin 22. Ground that puppy and you will bypass the park/neutral that is no longer there. If you want to wire in the clutch cancel, that can be done but it will take a little time.

And here is the '96. I guess it didn't want to do both at once.

Now I'll take a look at the reverse light. Watch this space.
 

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Thanks TheDurk I have been impressed by your 4runner knowledge on this forum. I am assuming he did not replace the wiring harness in the dash and replaced the engine harness and ECU. If so three of the engine harness plugs go right into the ecu and one has to be repinned. The problem is the park/neutral switch wire can't be repinned, it is the only wire that runs a completely different circuit from the auto to manual. He needs to find the park /neutral wire and run that over to the clutch start switch which is a ground switch. Or he could simply ground it and it will always start
 
I'm not sure what went wrong on the back-up light. It should just plug up. The circuit on both years, auto and manual both, goes through the same pins on the same plug. It's the I13 plug by the ECU, one of the two that goes to the truck not the ECU.

Here's what you need to check. 12V+ Power comes from the Gauge fuse at PIN 20 on a black/yellow wire and goes on to the reverse switch on the manual trans (or the Park/neutral, when it was there). When switch closes, power returns on a red/yellow wire to the same i13 plug at Pin 19 and goes on its merry way to the back-up lights.

This is buried in the Overall EWD for both years which are big docs. I don't have the simple diagram of the back-up lights so I can't post it. But this should allow you figure it out. Problem is one of three:

No power in on Pin 20
Switch not connecting between Pin 19 and Pin 20 (Maybe your harness transplant did not include the leg to the switch on the trans)
Something wrong in the light circuit between Pin 19 and the lights.

Thanks to [MENTION=78000]zgensler31[/MENTION] for the '96 and '98 EWD's. If he sees this, he may have advice on the back-up light connection.

Here is his thread, if you haven't seen it:

http://www.toyota-4runner.org/3rd-gen-t4rs/155303-possible-5-speed-swap-input-appreciated-2.html
 
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Thanks TheDurk I have been impressed by your 4runner knowledge on this forum. I am assuming he did not replace the wiring harness in the dash and replaced the engine harness and ECU. If so three of the engine harness plugs go right into the ecu and one has to be repinned. The problem is the park/neutral switch wire can't be repinned, it is the only wire that runs a completely different circuit from the auto to manual. He needs to find the park /neutral wire and run that over to the clutch start switch which is a ground switch. Or he could simply ground it and it will always start

Where I told him to ground the black/red is common to both the auto and 5-speed circuits in those years, and will completely bypass the interruptions for park/neutral or clutch switch--guaranteed. The loop is different, but the start and end points are exactly the same. IF he wants the clutch pedal switch and cancel switch, he pretty much has to go in and install those from zero. I'm waiting for him to tell me if he wants to go that route or do it the easy way.

In any case, I'd start by grounding as I described just to make sure that this is the issue and get the truck running.
 
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Well guys, I posted up this question a little too early. I called over buddy of mine. We traced out the wires & bypassed the clutch safety switch.

Truck will now start with the ignition & we wired up the remote start the proper way!


Today, I just have to put the hood on, bleed the clutch, tighten the exhaust bolts, finishing glueing down the new carpet, put the front seats in & put all of the Wood grain trim in :)

I do thank you all for the quick responses!


Oh and in say about 2-3 weeks, the TRD Supercharger will be on its way :)
 
Where I told him to ground the black/red is common to both the auto and 5-speed circuits in those years, and will completely bypass the interruptions for park/neutral or clutch switch--guaranteed. The loop is different, but the start and end points are exactly the same. IF he wants the clutch pedal switch and cancel switch, he pretty much has to go in and install those from zero. I'm waiting for him to tell me if he wants to go that route or do it the easy way.

In any case, I'd start by grounding as I described just to make sure that this is the issue and get the truck running.



I decided for now, just to bypass the Park/Neutral switch. It seems easier at this point and being without a truck for a few days has started to takes its toll on me!
 
That's funny. Durk thought I could help. Lol

Since I used the auto ecu and harness my reverse lights were simple. Take the two wires going to the switch on the auto Trans and plug them into the switch on the manual Trans. If I recall correctly they were even the same plug...sorry bro but you'll get it figured out. Don't lose faith.
 
OP I Don't know where you bypassed the park/neutral switch but if you take that b/r wire and run it to the clutch start switch on the bottom of the clutch pedal then run the w/b to a ground it will start only when you press on the clutch. I don't know if the safety factor is a factor for you or not. The clutch cancel switch will be very difficult because you have the 4 wire switch on the 98 and the 96/97 have a three wire switch
 

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