My swap consists of a 90 4runner 3.0 5spd and a 99 taco 3.4 5spd engine ($500) with zero accessories. i also have a 97 3.4 auto form a 4 runner that was tore down for rebuild by the p.o. ($100) that came with a few boxes of misc parts.

my plan was to use the 99 as it is assembled and the wire harness that came with the 97. so i bought a 97 auto ecu off ebay for $125 but the plugs arent even close to the harness i have.

so my question is can i use a complete m/t wire and ecu from any year that was 3.4?
i see that the 4runner was the same from 96 to 02 and the taco from 98 to 00. so if i use a 3.4 ecu and harness (that match) wouldn't my 99 taco engine just run under the year of ecu and harness that i use?

i know that a auto ecu can be made to work aswell. so if that is the case and my 99 could run under a 97 ecu couldn't i just find the right ecu or harness for either of the two that i have already?

 

you need a matching harness and ecu. At this point your 99 motor is just a long block correct? or does it have the harness with it? If you have the manual harness find a matching ecu for that.

 

correct just a block no harness. the answer i guess that i'm looking for are what options do i really have?

 

well look for a part number on the harness you have now... and go to the dealer and see if they can give you a part number for a matching ecu. Or try to find a harness that will match your auto ecu. Post some pictures of your plugs on the harness and the plugs on the ecu.

 

Ideally, you'd want the ECU and harness to be from the same year/tranny. There were a few changes to some of the wiring harness between model years, and even during model years.

What part of BC are you in?

 

I live in Vancouver. But doing my swap in Williams Lake.
All I have here for a pic is the one from ebay of the ecu.


I am really considering buying another wire harness and ecu from a m/t 3.4 if it is more worth while when it comes to wire chasing.

There must be some one out there who has done this swap with mix year ecu and engine?

 

IF you can find a 1997 M/T ECU then you would be golden with it and the 1997 manual harness

 

I got my engine and ECU from these guys in Westbank http://www.autorecycling.com/

Contact Phil and tell him what you're trying to do. He's the one I got my '97 Taco engine from.

 

i think i can find one locally but if not i will, thanks man.

but am i right that i can use my 99 engine with a different year ecu and harness?
99 seems to be the toughest to find.

 

as long as you use the electronics from the 97 you're good. The block internals, heads and intake manifold are the same. Throttle bodies changed as well as some of the sensors and such.

 

ok, so i should use the the 97 throttle body instead of the 99? which sensors changed?
wasnt the 4runner engine the same from 96 - 02?

 

I have a 2000 motor with a 97 manual ECU and harness. Everything is the same and just plugged in. The difference comes into play in the 2003 or so when they started to use electronic trottle

 

thank you

 

Some early years have a 4 wire TPS. EVAP sensors differ slightly on early 96 models. Try to get the 3 evap sensors with your harness and ecu. If you plan on running your CEL.

 

maf changed a little at 2000.

 

Have that from the 1997 also

 

That was 1999,

 

CEL?
On the evap topic, is it necessary? cant i just use the 3.0 system?

 

Check engine light

Yes you can, there are many right ups on how to do it. You still need some of the VSV's from the 3.4 system though

 

I'm not running it at all. I'm sure I have some code or another, but my CEL isn't hooked up, either.