Phroze2006

First of all this is going in a 1992 4runner where there once was a 3.slow auto.
K im getting my shopping list going here for my swap, I found a 1997 3.4 that was a 5speed and it comes with the engine harness. The question is will I need to get the ORS swap harness or will I be fine with the factory 3.4 harness? Also I hear that when doing the swap and installing the 3vz's 5speed that the clutch slave is on the opposite side, will this matter? When ordering the clutch assembly and using the flywheel which ones should i use 3.0's or 3.4's.... Thanks for the help

mt_goat

The 5VZ engine harness won't plug into the 92 4runner's body harness and the body harness won't plug into the 5VZ ECU, so yes, you still need a full conversion harness to mate them all together.

Here is lots of info:
http://www.offroadsolutions.com/technicalarticles.htm

breknraj

And, if you are going to do it yourself, you are going to need the body plugs from the 3.4 ECU, so that you can do the pin-out conversion from your Runner to the new 3.4 ECU. The Factory Service Manuals for both your Runner and the 3.4 Donor will be invaluable to figuring out the wiring.

I would recommend the ORS harness for speed and convenience, unless you are VERY comfortable with electrical wiring projects. It may seem pricey, before you do your conversion, but it made mine very close to a plug and play project!

BTW: you will read about sourcing all of your parts from the same donor. It will save you all kinds of headaches to do it that way, if at all possible! Read the various threads about swaps that have been done, and you will get a good feel for the kinds of things that you may run into. Search for mtgoat, fallman, myself, morphiasx, among others.

Phroze2006

So no matter what I do I am going to need the original engine harness from the 3.4 the ORS swap harness is for the dash harness correct?? I dont know if I should tackle the wiring although I have completed an SR20DET swap into a nissan 240sx in which i didnt have a swap harness and it was from a right hand drive but only had about 12 wires to be spliced and swapped. Don't know if that makes me competent to do this one or not. Thanks for the great link Goat.

breknraj

You'll want the engine, ECU and engine wiring harness from your donor. It would also be wise to get all the bolt-ons on the engine (alternator, intake, A/C compressor, PS pump).

There are also small parts that you will need for the evap system. All of this is covered very well on the ORS site.

You will also have to decide how you will do your exhaust, since the 3.4 is a mirror image of the 3.0 in that regard. There are many options that you can consider, depending on how you will use your truck, whether you need to smog it, what year donor you are dealing with, ect.

In addition, you'll be needing a Taco clutch kit, except for a 3.0 throw out bearing.

Good luck! You'll love the difference it makes!

RobD

I did the swap on mine without the ORS harness. While the ORS harness would have made it easier, I'm cheap. I swapped a 3.4 from a 97 Tacoma into my 1991 4Runner. They included all the parts from the Tacoma that I needed, except the EVAP, which I don't need (no smog test here).

The wiring went as such, for mine: the computer that came with my engine had three plugs wired to the harness. No problem, they just plug into the back of the computer. The 3.4 manual trans computer is in the pic on the left. The three plugs that came with the harness are in the center pic.

I was stuck for the fourth plug, though, as I had no idea where it was. It didn't come with the harness. But the 3.0 wiring harness did, so I cut it off there. That one you have to splice about 8 wires into, for example the battery, ground, etc.

RobD

You'll also need those two larger, square plugs (the white and gray) from your 3.0 harness. If memory serves, the wiring diagram calls those IH1 and IH2. Your 3.4 harness, they're probably called IK1 and IK2.

They're in the passenger side kick panel. Those are the ones you'll need to splice into your 3.4 harness. You'll need good wiring diagrams for both motors (www.techinfo.toyota.com). From there, it's a matter of going between the two harnesses and figuring out which wire on the 3.4 does the same job on the 3.0, like your water temp gauge, your oil pressure gauge, speed sensor, etc. A lot (but not all) of the color coded wires do the same or similar function in each harness.

You'll also need to find your starter relay wire and run it to the starter motor. I spent a couple hours tracing that one down. You'll also need to save your alternator harness from your 3.0. Don't go wildly chopping it out. When I started my engine for the first time, all ran well, but I wasn't getting any charge. So, I had to splice the 3.4 plug from the alternator onto the 3.0 harness.

RobD

Yeah, I had a crossover built while the engine was still out of the truck. The Tacoma dumps the exhaust down the passenger side, but the 4Runner's fuel tank is in the way, so it has to be dropped down the driver's side. I tried to cheap out here and have them use the exhaust flange from the Tacoma. After wasting $200 and a couple hours of time, I realized it was too big and going to hit the framerail and firewall...so, out came the engine and I had them re-do it. If you have a custom one done, make sure they have it stay tight to the back of the engine block and around the bellhousing. The second one fit perfectly and you'd swear it was factory. As for O2 sensors, I had them put in regular threaded bungs and I spliced generic O2 sensors onto the plugs. You can get O2 sensor bungs that will accept a Toyota bolt in O2 sensor from http://www.sleeoffroad.com/products/...driveshaft.htm

I'm running a high flow cat and muffler. The entire exhaust system was fabbed up by a guy named Bob at Jerry's Carline Muffler in Kelowna and he did an outstanding job. Whole thing, including crossover, high flow cat, and muffler ran around $1000. Pricey, maybe, but it needed doing and it sounds great.

And I agree, you'll love it.

Phroze2006

The ORS swap harness is way too pricey for what it is imho, I could make them and sell them for half and get rich muaaaahh muaaahhhhh, but seriously how hard could it be its just the one dash harness if what i'm seeing is correct and if its like most dash harnesses it has the power for the ecu and gauge wires running through it.

breknraj

If I had a garage to work in, I might have tried to do the conversion harness myself, but I don't, so I went with the ORS harness. There is a lot to be said for being able to call Mike, give him the pertinant information about the donor and recipient trucks, and he makes a custom harness for your specific application. Remember, there are a number of variations that have to be compensated for, since he is doing it as a business. Each year of truck, Tacoma and 4Runner will have slight differences in the wiring, so my '02 Tacoma manual to '90 truck is going to be different than someone else's '98 4Runner to '93 truck. Mike already has all the resources to do that, and he makes a quality product, so I'm glad that I took advantage of it.

If all you consider is the cost of the materials, then you must think that your personal time is free. If you actually attach a cost to your research time, cost of the FSM wiring diagams, build up time (and have the wire lengths right), getting all the pin-outs right, then the cost makes a lot more sense.

Doing the conversion harness is going to cost you. It will be either time, or money, but it will cost. My priority was time, so I spent the money. YMMV.

Phroze2006

Well ive got the time and I am very willing to spend it and spend it well, as far as money goes yea I am a cheapskate lol but thats what makes me more willing to spend my time to learn about the task. Is there any FSM's in pertucular that I will need for the pinouts or will the chilton at the library be good enough?

breknraj

You'll need the FSMs for both your recipient truck, and the donor vehicle (specifically the wiring diagrams). The paper FSMs are VERY pricey, but you can also download the info from Toyota - do a search for the link - you should be able to get all you need for the price of one day's membership.

As far as I'm concerned, Chiltons and Haynes aren't worth the paper they're printed on, especially for a project like this. You are going to need specifics, and those manuals deal only in generalities. The real deal from Toyota is the only one you'll ever need, and Toyota makes some of the best FSMs that I've ever seen - great pictures and explanations, and very good trouble-shooting procedures, as well.