1UZ into a VN (ALMOST COMPLETE, NEED HELP!)

[luke454]

Well, I’m almost there. In two weeks I have performed almost a compete conversion on a VN commodore from a 3.8 V6 to a 96 1UZFE out of an LS400. I'd have to say the hardest thing was fabricating the extractors. I tell you what, there is no room to be running any descent flowing pipes. It’s a log style header or nothing. The engine mounts weren’t tooo bad. A bit tricky but I got them in the end. As for the tail shaft, I haven’t finished that yet, I'm contemplating whether or not to use that dickey rubber block in place of a uni. I don’t want to but it might be the easiest and quickest way yet.



My recommendations for anyone attempting this conversion on a VN is, if you have a VN with a V6 in it, get a V8 cross member! Either that or use a plasma cutter and an FBH, that’s what I had to do. I didn't realise that the V8 cross member was different (son of a....) and don’t go into the conversion thinking you might be able to get out of it without making extractors. The only way you might be able to do this is if you relocated the splined collar connecting the steering arm to the rack, down further to where the shaft starts on the rack. Then you might be able to maintain those stock heaps of poop with only slight modifications, but even then I'm not sure, it would be very close. Anyway, enough of my waffle, Ill put some pics up soon for you guys to check out.



There is only ONE PROBLEM though. WIRING! I am really having a hard time getting a straight answer here. My question is how do (or where can I find out) how to start it? I have the wiring diagrams etc but as it stands, it will take some time to translate. I am running (regardless of weather I can or not) the standard ECU and harness.

I’m only new to this 1UZFE business and the copious amount of blasted wiring they have, so bare with me.



So my question stands at:



Does anyone know what wires I have to run to my original fuse box to the standard 1UZFE harness get this sucker running?

 

[Zuffen]

Luke,

I don't know what engine you're using so a firm answer's hard to give,

If a Crown look at KDogs threads as he posted the pinout for a Crown and it's easy enough to follow. I did so that says a lot!

If you're using an LS or SC engine check out the tech section on the home page as it has wiring diagrams that are quite easy to follow.

Best advice is draw what you have to do (with colours etc) so you can put it into practice. You don't have to be an electronics guru to make it run.

 

[luke454]

I am using a 95/96 model 1UZFE out of an LS400, well, trying to. I have checked out those wiring diagrams so ill see how I go. Also, this motor has provision for a hydraulic thermo which I will not be using. Do you know if I can just plug these lines up? Im thinking that it will probably operate on some form of temperature sender so if I dont hook the wires up it shouldn't kick up. Is that right?

 

[krayn]

Luke, How many plugs go into the computer and how many pins on each connector. I had a 96 model crown but the wiring was similar to 96 ls400. I made up my own wiring loom by following the 96 ls400 diags. The only wires I needed to make it run is a wire to batt + ve, ignition, start wire, and fuel pump wires. There are other wires that can be connected up like stop light switch, reverse light, tacho, speedo, park light input, power swich, overdrive swich ect. My advice is that there is no real easy way to get it to run without connecting up the relays ect in the way the origional works. Follow the wiring diags for your style of ecu and chase out each individual wire. it is time consuming. if this is all too much you may need to pay someone to do it who knows........

 

[luke454]

By following the wiring diagram I have managed to get it to turn over but I have no spark. I have run the wires to the ignition (blk/red) but still have nothing. I'll keep pluggin away untill I get something. It is reassuring that I only have to hook up a few wires though. As for the plugs, I have 3 plugs that go into the computer which are much the same as what is in the diagram. If your setup is wired up the same as the LS400, do you remember (if you kept the same colour coding) what colour wires you hooked up to start it? I just want to see if im on the right track here, this is my first attempt at wiring something up of this magnitude.

 

[Zuffen]

Luke,

The best thing with the Hydraulic pump is to strip the vanes out of it and connect the inlet to the oulet with a little oil in it so it doesn't seize.

Don't forget your igniters must be earthed to get spark.

You need to connect the different earths coming out of the ECu (probably 3) and you have 1 permanent +12volts and (I think) two +12volts which are switched.

Other than that you need the start wire and fuel and it should run.

 

[krayn]

Luke, Like rod says, make sure you have an earth to your ignitors. I had this exact problem and when earthed it fired up. Also when I was setting mine up I tried just hooking up the wires and not using relays ect like the plan shows. I figured it should still work just to start it but it didnt. With mine (which is different to yours as my ecu has 4 plugs) I had to hook up the relays as shown. Aparently there is a sequence that the ecu likes to see on its power inputs. It was a while ago but I think that when ignition is applied to the ecu, if all is good the ecu then turns on the main power relay to the ecu, and this then allows the engine to start. Not sure if yours is the same in this reguard. I do know that I tried what you are doing but it didnt work, but when I sat down and split the loom to the engine chased out where all the wires went to, labled them all (as the color code was different to the diag), made a wiring loom which is fairly simple loom just 5 relays and a fuse box, hooked it up and it went first go after earthing the ignitors. good luck, Kris

 

[luke454]

well, I have got it running but its running like a hiry goat. One side of the extractors start glowing after about 5 mins of running and its pretty unresponsive. I cant figure out what the hell is going on here. The only thing that may be a problem is that I am suposto have 4 oxygen sensors (apparently according to the wiring diagram) but the problem is I only have two. The excessive heat in the exhaust indicates to me that the is a timing problem but other than this, I have no idea what the hell is happening. As you said kris, the wires tend to change colours all over the shop, so maybey I have missed something somewhere. Perhaps I can bridge the oxygen sensors to fool the computer that I actually have 4? has anyone done this? I think ill have to start again, If I wasent pressed for time i think making up a loom would be the way to go. The way I have wired it up is not the same as what is in the relay setup but effectively does the same thing so perhaps, if what your saying about the relay setup is also a -problem area then Ill have to set it up according to the diagram.... Thanks for your help guys,

Luke

 

[KDog]

It should run fine without the oxy sensors, it will just pop some error codes and if none are there it will not run in closed loop.
Sounds like you problem is serious. I would not run the engine until you have its sorted.
You should be able to get the LS400 diagrams from a lexus dealer. Until you have them and have checked all the wiring I would not continue.

 

[Peewee]

Have you had the injectors cleaned?
When I first drove mine, after a 2km drive, the cat was glowing red, and the rear bumper was melted.
Car had no power either.

Got the injectors cleaned (guy reckons most were ok, only 2 were 15% blocked), and it suddenly had 250hp.