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Gert Roewer

1 UZ FE Wiring.

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Hi everyone, Gert here from Jindera in Australia.    You Kiwis have always impressed me with your innovation and inventiveness.  Shades of Bert Munro.  I suppose it may have something to do with being isolated in the lower part of the Pacific miles from anywhere, sand having to be largely self sufficient.  Anyway I am a new member and I like the theme of this group.  

I am a long term trike builder and have been working on my current project for a few years, on and off, but now have decided to get on with it and finish it.  It's a trike based on the drivetrain of a 1992 Toyota Soarer SC400 with the v8 engine  1UZ-FE.   The ECU on this model has 3 plugs each with 40 pins.  I have chased and connected almost all the the wires to the various sensors, power supply etc. but I'm stumped by a couple and was hoping for a bit of a chop out here.  Nigel Wade wrote an article on how to wire this up and posted it on the internet, but it assumes you have access to factory wiring diagrams, which I don't, and am finding impossible to get.  Nigel led me to this group and said he was a member, but a search of members doesn't seem to reveal his presence.  The stumbling block in this build is that I need pin No's on the ECU for the O2 sensors, and  a pin No. for Battery 12Vpower for the memory.  Other than that it's all go.  I haven't tried to start the motor as yet because it's not going to run very well without the O2 sensors (2).  Can anyone help?  Nigel, where are you?

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I've got the SC400 1992 ecu diagram. I got it two years ago, so memory is hazy. I think I might have got it off the links provided by Nigel on an ancient forum post. Most links were broken, but with lots of digging and guess work using some of the still working links, I downloaded everything I could find.

PM me your email address and I'll send the diagram, I don't think I can post PDFs on the forum. 

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If you just wanted to run the trike for now, I wouldn't be worried about the 02 sensors. 

I had a 92 UZZ30 and unplugged the 02 sensors and afm when trying to narrow down an issue. It ran mildly more rich but still ran great. 

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Yeah, it should start fine with no O2 sensors plugged in. Some Toyota ECUs have the pins labeled if you pop the lid off.

There are a few V8 trike fans around this place too...

image_zps78eggkmu.jpg?width=480&height=4

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Nigel was here a long time ago but got the shits about something and deleted a lot of his posts.

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Thanks guys.  Yes I'm aware that it should start without the O2 sensors, but it won't run as it should so I really need to hook them up.  I also need to give the ECU a direct connection to the battery, but which pin?  I can't believe how hard it has been just to get a clear wiring diagram with pin No.'s on the ECU.  Still haven't got what I need.    Does anyone know how I can Contact Nigel?  I reckon he might be the man with the answers.

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20 hours ago, kicker said:

Nigel was here a long time ago but got the shits about something and deleted a lot of his posts.

Is there any way of contacting him?

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Hi fellas,

Just an update.  I got all the diagrams and wiring instructions from the Lextreme site and followed them implicitly.  Got spark but no injector pulse.  I sent the ECU to the Soarer Surgeon and he tried it in a car and it ran the car.  He freshened it up for me and while it was away I was checking my wiring for the 43rd time when I realized that the cold start injector was not hooked up to the starter.  I fixed that and when I got the ECU back, put it in and whammo it started immediately and settled into a very rough idle.  However the slightest touch of throttle and it would stall.  Got the noid lights out and Damn, still no injector pulse on any injectors.  The injectors are all powered but the ECU is not switching them.  All the sensors are correctly connected.  I am using the sc400 original loom as far as I can.    All earths are earthing and all power wires to the ECU are powered.   Because I am using the factory loom I can't imagine that I have reversed polarity on the cam and crank sensors.  But if this were so, would it stop the injector pulse? (It has spark).  I am not a dill when it comes to wiring and have been doing my own wiring for nigh on 60 years, but I'm fast reaching a dead end here.   Any help or suggestions would be gratefully accepted.  I  know it's not the ECU so it has to be something in the connections.

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Dunno if this has been covered before but check that the injectors aren't stuck.

It's a common problem. 

Power them straight of 12v and make sure you can get then ticking open and closed. 

If they've been sitting for a while they will stick

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I haven't checked cam and crank signals at the ECU.  I assumed that with the spark being okay that the cam and crank sensors must be giving correct signals.   But I don't know if the coil igniters read these signals directly or via the ECU.  I will check at the ECU in the morn.  Good tip thank you.    As an aside, I didn't have the original coil igniters, and finished up getting igniters #123 from a Corolla.   They are supposed to be okay as a replacement.  But in any case tomorrow I am going to remove the igniters from my 89 Celsior and try them.  My understanding is the ECU reads the igniters for injector pulse.  Is that correct?  This is all a little deeper than just reading a diagram and I'm getting really tired..

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Well with a bit of help from the internet and fellow travellers I seem to have at long last sorted out the wiring and problems I have been having.  It's been a slow laborious process and I have had to deal with incredible frustration at times.  The experts in the field have been very kind in making wiring information available and without them I would have had to pay someone to do this.  After having wired the original sc400 loom with some practical modifications, and still not getting an injector pulse, and making my plight known on this forum and elsewhere  I tried a few more things today.  Just in case the coil igniters had anything to do with it, I swapped them for the ones off my 89 Celsior.  That made no difference.  I also checked with a multimeter to see if the cam and crank signals were reaching the ECU.  They were.  It would start easily and idle very roughly just on the cold start injector, but strangely, shutting the ignition switch off didn't stop the motor.  I had to disconnect the battery to stop it..  A bit of poking around with a test  light showed that the three relays I had installed to power the Igniters, injectors, and pin 24 MREL on the E9 plug would not shut off with the ignition switch.  Normally on pin 24 this is 12 in from the man efi relay.  I don't have an efi relay so I powered it from a 40 amp relay switched by the ignition switch.  Once activated, all three relays refused to shut off with the ignition switch.  When I removed the relay that was powering pin 24, the remaining two performed normally and shut off with ignition off.  On reading the instructions once more, it seems that the author had had the same problem.  So I did what he did and wired pin 24 directly to the output of the ignition switch.  We then tested for injector pulse with a noid light  and it lit up like a Christmas tree.    We then started the engine and all 8 injectors were firing.  I disconnected the cold start injector and it still fired up.  Finally.     

However as the old saying goes, "One door closes, and another one shuts.  (Ha ha!)"  I had originally bought the engine in a half cut about 9 years ago from an old guy in Newcastle NSW and he had bought it about 10 years previously and had used a few things from it.  It had been left uncovered with the bonnet off in the weather and it was pretty grotty.  But I figured it was only cosmetic and took a punt that the engine would still be okay internally.  It should have been.  I have never had the engine started until now.  When I first fired it I immediately noticed a loud tapping noise coming from the inside of the motor.  I have heard this kind of noise many times in my life and it wasn't good.  Sounded crank/piston related.   But I wasn't too concerned because the plan has always been before the trike is actually put on the road to do a full rebuild of the engine.  While we were fooling around getting the engine running  and starting it up several times all of a sudden the tapping magically completely disappeared.  That put a smile on my face because the thought went through my head that whatever was causing the noise had rectified itself.  So I took the revs up a little and the smile on my face disappeared as quickly as it had appeared.  The floor of the shed was sprayed with metal shrapnel and oil as a conrod/piston assembly let go and found its way to the outside world via the sump and the side of the block.  Bugger!!!!!  Well at least it lasted long enough to enable me to sort the wiring.  I have a spare engine and am looking forward to rebuilding it.

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