Building a 1UZ into an MX73 Cressida.

[AndreO]

Hello Everyone,

I need your guidance please, especially those of you familiar with the 1UZ's and the MX73's.

Here is my story, and I'll keep it as brief as I can:
I recently had the misfortune of seeing the 21R motor in my 1986 Cressida (MX73) go pop on the way to work one morning.

After much phoning and searching for another 21R or even a 22R I cannot find another 21R in my local area in South Africa. I was quoted on a 22R motor, but that was for about as much as what I paid for the whole car!!
So my next option was a conversion, and lo and behold, a local used motor dealer has a 1UZ, with it's auto 'box and factory computer for what is a genuinely reasonable price. Since my car is currently automatic I figure this is an ideal transplant.

I am fairly competent in the workshop, but am seeking advice as to the pitfalls I need to watch out for and in particular, getting the wiring correct first time around. My budget does not allow for 2nd chances.
After a bit of searching through the forum I decided to join up and seek the help of all you sages out there.

My plan is figure it all out and once I know all the in's and out's and have all the parts together, do the job as quick as I can during December.

Any and all advice will be much appreciated.

Andre

[CrUZida]

Have a search for the 1UZ into MA61 thread, it will help tremendously

[AndreO]

Thank you very much,

I found the thread. It'll help very much for the physical install. I cannot see any issues with that.

My next question is where can I find solidly reliable information regarding the wiring of the ECU. My 1UZ will come with the harness cut as in the picture below: (I hope the photo shows up okay)
LEXUS 1UZ-FE 4.0 V8 LS400.jpg
My Cressida's will be complete as for the 21R Carburettor Electronic ignition configuration. So I can cut and splice as required.

This is my biggest concern as I want to do this absolutely properly.
The car does not have cruise control, and my understanding is that the ECU may have this facility. I do not feel that this is a critical requirement for me, but I need the car to run every weekend. ( I ride a motor bike to work every weekday, unless the bike goes in for a service, the car is solely for family use on weekends)
When we do take it out, it runs for a minimum of 100kms per trip.
All I need is for the motor to run reliably, and have use of the aircon. Warning lights, auto box, gauges etc are of course vital too.

Thanks again.

[CrUZida]

There is a wiring diagram thread on these forums. Also try v-eight.com and lextreme.com for other wiring diagrams. Google is your friend.
You will be able to find everything you need to know about the 1UZ without too much difficulty (you may have more issues finding details about the RX71 wiring).

Cruise Control is separate to the engine and gearbox ecu's, so don't worry about it.

[AndreO]

Thank you CrUZida,

I have googled some info last night. I have much to digest.
I think I have enough info at the moment to see me through, all should go well.
Once the job is started I shall take photos and post updates here for reference should anyone else do something similar.
Once I sort all my info and can vouch for what is correct for this conversion I'll post it up here too.

[robson r v]

Hi AndreO. Did you ever come right with wiring diagrams for the 1UZ. I am doing a transplant of a 1 UZ vvti and also need diagrams. Can you help? Please mail me at [email protected]