jakes_runner

Hey everyone I just bought a 90 runner 4x4 5 speed manuel with a blown motor and trying to figure out what to do motor wise. I had some questions about the swap that im sure someone knows the answer to. When purchasing a 3.4l does it have to be out of a 4x4 vehicle with a manual or can I just swap out the ecu of the same year to make it work with my stuff? Are all of the wiring harnesses the same? And I was thinking about keeping the tyranny that is in it now but im not sure if the ecu will be happy with that?

jakes_runner

back to the top!

Kutter

You can really get the motor from anywhere. The ECU and wire harness and electrics are the important part to match together. It is most safe to get everything from the same vehicle though to be sure of compatability. Many differences in ECU, wiring, TPS, MAF.

ECU and electrics must come from manual 4x4 for your application. 1998 and 1999 are good years for the 3.4 to use in a swap.

You can keep your tranny with no problems.

PM and I can send you pic's of my 3.4 swap if you like.

It is not to hard to do and does not take a long time if you are mechanical type. Mine was back on the highway in 50 hours of labor.

kt19

Kutter
I'm thinking the same thing about doing the swap and I have access to a 98 4 -Runner w/ an auto but it is 2 wheel. I have a 90 with an auto planned on using the same tranny in the truck and swapping the motor. Will the ECU in the 4-runner work in my application or will I need to get one from a 4-wheel truck or runner. I've read thru a few write ups on here and it seems that getting or building a new harness is a must so that doesn't concern me as much as the ECU swap. Just searching for a little more info because I can get this donor real cheap.

Toyota-san

Thinking about keeping the Tyranny huh?

A tyrant possesses absolute power through the people in a state or in an organization: one refers to this mode of rule as a tyranny

Good luck with that...

Kutter

First off the 3.4 swap is always a good idea IMO.

If the 98 2wd is a really sweet deal why not jump on it. It will cover alot of your mechanical parts required. Such as, engine, ignition coils, starter, powersteering pump, a/c compressor, fuel injectors, rails, intake manifold, throttle body, starter. Sell off the parts you don't need. I paid $1600.00 for my engine and ECU, engine harness, battery harness, evap canister, plus all evap vsv's.

You will need to get an ECU, engine wiring harness, battery harness, and transmission with transfer case from a 3.4 4x4 automatic donor. This stuff needs to match. Usually easiest to get it all from the same donor to ensure no surprises. Probably a good idea to also get the other electric items from this vehicle too to be sure they match what the ECU needs to operate correctly. The 3.4 ECU will not run your existing 3.0 auto tranny correctly according to ORS tech article. See ORS.com

You may be lucky. Check and see if they TPS, MAF are the same for the 1998 2wd and 4wd. I know there were changes between 1998 and 1999. I had a free 1998 2wd MAF. I tried to install it in with my 1999 4x4 ECU. It ran but not quit right. Poor idle and used too much fuel.

You need the two 3.4 wire harenesses. On top of that you will need to buy or make a conversion harness to link the 3.4 harness to your vehicle's existing wiring so the ECU gets all the right signals.

I did a swap report on 4x4wire.com in the 4runner forum in December 06. Search 3.4 swap complete.

PM if you have a question.

Dan.3

I could be worng but the MAF doesnt matter if it is 2 wheel drive or 4 wheel drive. The MAF was probably bad. Im pretty sure the MAF is the same part number for 2 wheel and 4 wheel. I have no idea why it would be different. From what I have found the 98 and 99 is recomend by ORS because for the reason of the oil dipstick. You dont have to tap the block. It is very convient to pull everything out of the same vehicle but not every piece has to come from it.

Kutter

You may be right about the 2wd to 4wd MAF statement. It is however for sure different between 1998 and 1999. Hence my problem.