swapping in motor from auto transmission

GJCruiser · 08-13-2009, 04:44 PM

I know the swap can be done if the donor motor, ECU, and harness all come from the same auto trans vehicle and the 93 recipient is a manual. The part that I'm not clear on is what to expect regarding transmission error codes thrown? Will there always be trans. codes thrown even if fooling the ECU into thinking truck is always in neutral or does that neutral "trick" remove the codes?

thanks very much

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GJCruiser · 08-18-2009, 11:23 AM

Realize I asked this question badly. Let me try again.

Background-difficult to find manual-equipped trucks or 4runnners here to use as donors for the 3.4 swap into my 93 manual truck. Much more common are automatic equipped 4runners.

What problems does anyone know exist in trying to use motor, ecu, and harness from an auto-equipped vehicle? I've seen the question raised here but not answered. Potentially issues with some feedback signals from teh transmission being used for engine fuel management?

Anyone have firsthand experience or schematics that definately show signals running from trans to ecu?

Thanks!

yodathespian87 · 08-18-2009, 01:19 PM

There are a few guys on here that have been able to do this. There aer I think around 3 threads on there builds. I don't remember them by name but they are out there.Best of luck.

GJCruiser · 08-20-2009, 03:34 PM

Thanks for the reply. I'm assuming that it's not easy to simulate the solenoids in the transmssion. Even if I can, I don't know if there are critical timing issues during shifts that may trip a CEL. It's not as simple as swapping only the ECU because they're pinned differently between the manual and auto versions. So then, buy manual ECU and harness connectors and then re-pin the whole harness? I'm not even sure the connectors and pins are available. I've got a lot more work to do!

thefallman · 08-27-2009, 03:58 PM

Got a better idea for you get on Car-part.com and find a ecu and harness for a Manual fairly easy to do especially for manuals. fairly cheap too under 200 for both.

GJCruiser · 08-28-2009, 09:43 AM

thanks for the idea. your suggestion may be the easiest way to proceed. I'll have to stay close to the year of the motor for the ecu and harness so that the motor end of the harness matches up with everything under the hood.

Thanks

dntsdad · 11-14-2009, 06:19 PM

man i wish people would update these thread so the rest of us idiots know how it worked out.

I have the exact same issue/question

thefallman · 11-14-2009, 06:29 PM

so get a harness from car-part.com and use it.

dntsdad · 11-14-2009, 06:37 PM

I would but i read so much that that may not work because of this and that. I searched them the other night there were a bunch of 97 5speed, 4x4 harness/ecm but wasnt sure that was going to work.

I cant see why it would not, but I am not an engineer.

If you know, why would just replacing the ecm with a 5 speed ecm not work and just not use the wires in my auto harness that are suppose to go to the auto trans.

This would save my the $150 or so for a 5 speed harness if i could just cap those wires up

UKrunner · 11-15-2009, 06:18 AM

I think this is fairly simple. Need to fool the ecu that the tranny is in park to start it. A high power resistor to ground will simulate a solenoid. The resistance of the solenoid coils is, I believe in the FSM.
I think that might be all you need. If you dont care about codes then you wont need the resistors.

08-18-2009, 01:19 PM	#3 (permalink)
yodathespian87 Contributing Member Join Date: Apr 2008 Location: Colorado Springs, Colorado Posts: 464	There are a few guys on here that have been able to do this. There aer I think around 3 threads on there builds. I don't remember them by name but they are out there.Best of luck. __________________ 86 Pickup 4x2, Manual (Sold) 87 Extra Cab Pickup 4x4, Manual (Sold) 93 4Runner 4x4, Manual, 3.4 Swap In progress 90 4Runner 4x4, Manual, Blown 3.0 (Stripping out for parts then to become a trail rig/camping/fun truck) 94 Lexus SC400, 1UZ, magnaflow exhaust, after market headlights, bought for parts for the swap into the 90 4Runner

08-27-2009, 03:58 PM	#5 (permalink)
thefallman Registered User Join Date: Jun 2006 Location: Walla Walla, WA Posts: 550	Got a better idea for you get on Car-part.com and find a ecu and harness for a Manual fairly easy to do especially for manuals. fairly cheap too under 200 for both. __________________ ~Brian GETTING FIXED 89 Ex-Cab 3.4 Conv. T100 Auto Tranny ~Phoenix 94 Ex-Cab 22re 5spd Came with parts truck. Doesnt run yet. 90 4runner 3.0 Auto (Wifes Toy) 92 4runner 3.0 Auto (Currently With Blown Engine) (New 3.4 Swap i think)

11-14-2009, 06:19 PM	#7 (permalink)
dntsdad Registered User Join Date: Jan 2009 Location: Fresno, Ca. Posts: 289	man i wish people would update these thread so the rest of us idiots know how it worked out. I have the exact same issue/question __________________ 1992 Toyota Pickup Ex-Cab 3.0 V6 4" Pro-Comp lift

11-14-2009, 06:29 PM	#8 (permalink)
thefallman Registered User Join Date: Jun 2006 Location: Walla Walla, WA Posts: 550	so get a harness from car-part.com and use it. __________________ ~Brian GETTING FIXED 89 Ex-Cab 3.4 Conv. T100 Auto Tranny ~Phoenix 94 Ex-Cab 22re 5spd Came with parts truck. Doesnt run yet. 90 4runner 3.0 Auto (Wifes Toy) 92 4runner 3.0 Auto (Currently With Blown Engine) (New 3.4 Swap i think)

11-14-2009, 06:37 PM	#9 (permalink)
dntsdad Registered User Join Date: Jan 2009 Location: Fresno, Ca. Posts: 289	I would but i read so much that that may not work because of this and that. I searched them the other night there were a bunch of 97 5speed, 4x4 harness/ecm but wasnt sure that was going to work. I cant see why it would not, but I am not an engineer. If you know, why would just replacing the ecm with a 5 speed ecm not work and just not use the wires in my auto harness that are suppose to go to the auto trans. This would save my the $150 or so for a 5 speed harness if i could just cap those wires up __________________ 1992 Toyota Pickup Ex-Cab 3.0 V6 4" Pro-Comp lift

08-18-2009, 11:23 AM	#2 (permalink)
GJCruiser Registered User Join Date: Apr 2009 Posts: 24	Realize I asked this question badly. Let me try again. Background-difficult to find manual-equipped trucks or 4runnners here to use as donors for the 3.4 swap into my 93 manual truck. Much more common are automatic equipped 4runners. What problems does anyone know exist in trying to use motor, ecu, and harness from an auto-equipped vehicle? I've seen the question raised here but not answered. Potentially issues with some feedback signals from teh transmission being used for engine fuel management? Anyone have firsthand experience or schematics that definately show signals running from trans to ecu? Thanks!

08-20-2009, 03:34 PM	#4 (permalink)
GJCruiser Registered User Join Date: Apr 2009 Posts: 24	Thanks for the reply. I'm assuming that it's not easy to simulate the solenoids in the transmssion. Even if I can, I don't know if there are critical timing issues during shifts that may trip a CEL. It's not as simple as swapping only the ECU because they're pinned differently between the manual and auto versions. So then, buy manual ECU and harness connectors and then re-pin the whole harness? I'm not even sure the connectors and pins are available. I've got a lot more work to do!

08-28-2009, 09:43 AM	#6 (permalink)
GJCruiser Registered User Join Date: Apr 2009 Posts: 24	thanks for the idea. your suggestion may be the easiest way to proceed. I'll have to stay close to the year of the motor for the ecu and harness so that the motor end of the harness matches up with everything under the hood. Thanks

11-15-2009, 06:18 AM	#10 (permalink)
UKrunner Registered User Join Date: Apr 2008 Posts: 158	I think this is fairly simple. Need to fool the ecu that the tranny is in park to start it. A high power resistor to ground will simulate a solenoid. The resistance of the solenoid coils is, I believe in the FSM. I think that might be all you need. If you dont care about codes then you wont need the resistors.

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