1uz fe Hovercraft


New Member
Hello everyone out there.

My first post here what a great site and incredible amount of knowledge.

I need some info of course, My 1uzfe just arrived and I am in need of ECU part number so that I can purchase one. I also am looking for schematics to build the harness. I have what is cut off from the engine importer on the motor side but will need the ecu plug or plugs as well. Is there a better source than www.car-part.com.

Being that i run in a salt marine enviroment i have to build the harness with tinned or silvered wire so that it wont corrode. These means a complete build for me. This will be my first harness build for a engine. I have a dry cabin to install the ecu in that is climate controlled with heat and air conditioning so i should be able to keep it in top notch shape.

I read on the forum some where that one model ecu is seperate from the transmission and runs with out the transmission ecu. Is this the way to go or is there a better route. I want to stay with all stock lexus parts nothing after market as it has more power than i can use. i expect the cruise rpm will be under 3500rpm and the engine runs like a tractor we almost never change throttle settings until its time to land the craft. on a tight river you may jockey it around a bit using the engine to steer a bit but its pretty much set the throttle and forget it. Usually we use 100hp less on a craft like this but i really wanted to expand the throttle envelope on this project.

i run a 3 to 1 belt drive driven off the flywheel side. the craft takes about 6 to 10 seconds normally to take flight. I'm hoping to keep this under 6 seconds or very close to it with the lexus power.

I'm happy to answer any hovercraft questions or give rides to anyone in my neck of the woods. I would apreciate any advice or recomendations on this engine as it is my first time using it.

Also would anyone like to trade me my toyota emblem for a lexus emblem? I'm using lexus emblems on the craft itself so i would really like to remove the toyota emblem from the intake and have it say lexus.

can you get a valve cover that has the four cam 32 valve writing on it as well to match the other side.

The late model trucks have a big plastic engine cover on them will that fit the 1uzfe? Does the lexus car have one of these? are the engines close enough over the years to be able to have the brackets bolt on? i dont mind some custome brackets just trying to keep it all stock. normaly i would build a composite engine cover but the factory stuff is so nice and simple.

Jeff Hart


"Supra" Moderator
Staff member
Hello Jeff, and welcome to Lextreme; what an interesting application you have. We have members with UZ's in their boats, experimental aircraft, trikes, etc. but I think you're the first to use it in a hovercraft.

There's a gentleman named Richard Welch who runs a business called www.autosportwiring.com, and he can build you a custom fly lead harness from the ECU connectors back, leaving any length you want of fly lead free. He does excellent work, and I presently use one of his temporary harnesses whenever I put an engine on the dyno.

There is also our member Dr. Tweak, who runs Phoenixtuning.com, who can probably build you a complete custom harness (from the ECU to the sensors).

I would think either of these gentlemen could do a good job for you, particularly if you already know what you want in the way of wiring, and/or if you can provide it to them.

Since you're only interested in running the engine, and not interfacing to any of the other "car" functions, I would think you'd be an ideal candidate for a cheap aftermarket ECU? Something like a Megasquirt? This would simplify your harnessing a lot, also. There are several members on here who have used Megasquirts for their setups and it apparently works well.


New Member
Thanks for the quik reply

I have spoken to Josh at Phoenix he seems to be the right guy to get one built. He was telling me he had all the new connectors and such if needed. But I was thinking since I was planning on this motor being my new main stay for craft that i would do the harness myself and let it hopefully help in future diagnositic repairs as well as save me some money.

Ive heard of mega squirt but was thinking if i have to go through the work of a harness and i'm not looking for any upgrades to performance a stock ecu would be the same or better for my application. I was really trying to stay in the area if the craft breaks down it can go to a toyota mechanic and be repaired and hime knowing its all lexus or toyota would not scare a tech off. also it is important to me to make sure as many parts as possible are off the shelf for service. I like the idea a guy is able to go to the parts store and at worse order the part or even go to a recycler yard if he had to for parts.

I'm not the first to use the 1uzfe in NZ they have been using them since they were new. http://www.hovercraft.co.nz/explorer/overview.htm This craft can be had with cummins deisel or 1uzfe.
http://www.youtube.com/watch?v=rVrT66mGJTY this video shows you the craft with the 1uz motor in a completly stock aplication running belts off the fly wheel to power the blades.
In my application i simply run the motor exposed on the outside of the craft.
So if i wanted to stay with a stock ecm which would be my best choice. Also doe the engine harness plug directly to the ecu or is it a sub harness to the ecu plugs harness.
Thanks again Jeff www.sevtecexplorer.com


"Supra" Moderator
Staff member
Toyota/Lexus ECU's are "locked" out to most mortals, so they're not very interesting for most of us when we start hotrodding this motor.

I can understand and appreciate why you want to stay OEM with this, and I wish you luck.

Perhaps some other guys can chime in on tips with using this ECU in a standalone, non-OEM application.


New Member
There is a bit more to just plugging in the loom you need to get a matching set ecu harness, MAF sensor, etc etc then you need to splice in the starting circuit. It has all been done before and the information and wiring diagrams are on this forum. Probably the easiest one for you to find would be the LS400 or SC 400 ecu and loom either will do the job.

Honestly though most of the OEM ecu's are getting long in the tooth now and reliability would be an issue. Parts for the OEM ecu's are not cheap off the shelf, try pricing a MAF sensor for one.

I'd love to see you hover into your local Lexus dealer and ask them to have a look at the old girl......

For cost effectiveness I would go aftermarket ecu, plenty to choose from and most can supply a good base tune to get you going. You won't need to hunt down old second hand parts this way. With your single rpm and load mode, tuning would be very easy with a wide band o2 sensor.

can you get a valve cover that has the four cam 32 valve writing on it as well to match the other side. NO.

Also would anyone like to trade me my toyota emblem for a lexus emblem? I'm using lexus emblems on the craft itself so i would really like to remove the toyota emblem from the intake and have it say lexus. They are around just have to keep looking and asking.

Keep us informed of your build and welcome to Lextreme.


New Member
Hovercraft... sweeeet! Hovercraft +1UZ = where do I sign up? I want to see this.

About engine management I would suggest using a standalone for sure. Yeah it seems expensive but you can almost plug and play them! I would suggest a Motec MLS computer. Any money spent on a factory harness and ECU that you don't already have it just torturing yourself trying to save money. I bought an Adaptronic with the guys here and I'm days from firing mine up... maybe hours. They have been working great for everyone so far. But a friend of mine in L.A. told me he was a dealer for Motec when he found out about me buying an Adaptronic! I couldn't believe it. I was pretty upset with him for not telling me this while I was asking him about some other electrical issues with the Lex ECU. He would have installed it for free and given me his pricing too.

Anyhow there are Motec dealers here in the U.S. and lots of available help PLUS the pricing is great for such a name brand and reputable product. They officially support the 1UZ with this computer... it's not just a generic product! http://www.motec.com.au/mls/mlsfeatures/

I wouldn't bother with the factory computer. You are going to be in some harsh environments and the harnesses that you will get from recyclers will be thrashed, cracked and broken. I wouldn't trust them and they will want a lot of $$. You would be insane to purchase an old used 1UZ harness to use on your build IMO. You don't want to be stuck in the middle of the swamp with a harness failure! Plus you can scrap all the emissions crap that just adds clutter to custom applications(and a lot more time to your fabrication).

I have a couple computers and a couple wiring harnesses from my travels into 1UZ land. There are a couple different versions of each for these engines. It's a pain in the butt and hard to just ID which one will work with which. It will be some custom work and lots of studying so get ready! I like wiring to be SUPER clean and to proper length and you just can't do this without cutting up the whole harness and almost starting over. I would fabricate the engine into place, measure out the distances to the components and then have Dr. Tweak (or whoever does the harness) make one nice and tidy. The price he charges is EASILY worth the headache and time spent studying how to wire and troubleshoot it. When you have a simplified correct harness from him it will be much easier to sort through than a stock harness that you have to pick apart yourself. Plus new connectors are worth every single penny. The old ones crack so easy.

Keep us updated!
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Super Moderator
Staff member
I'd go standalone for the reasons others have expressed.

PLUS you can get waterproof/resitant aftermarket ECU's.

I would use an Adaptronic (although it isn't a waterproof one) as they are priced well and work well.

Being in NZ a Link would be the obvious way to go.

If you plan on making more than 1 vehicle I'd source the sensor plugs and make your own harness. Any aftermarket ECU will come with the plugs for its end.

Doing it this way will give all new electronics and have an easy parts supply line.

Once the first engine is tuned all others are just a matter of uploading the tune to the new ECU.

An engine harness for your application would have less than 15 wires in t.


New Member
I'd really like to have one of these but it would mean i would miss this summer out on the water with this machine. Saving the money up that is.

When i decided on this motor it was the best priced all aluminum 200plus hp set up with people on line doing the conversons to the trucks and such and only running the ecu for the engine. Our budget for the ecu system was $300. www.car-part.com has used ecu's for $50 and we have the connectors on the engine we bought from www.engineworld.com. Josh from Phoenix tune said he could make a harness for us but it was out of our budget. he said he could supply us with any of the plugs we needed new so that gave us a source for connectors and we use silver or tinned wire for the marine application just incase one of the connectors dont seal up just perfect.

So what i'm needing to do is try and stay in the budget with a stock set up and down the road if it is a issue we can upgrade from there.

I have alldata so i think I have the pin out for the ecu's but i'm needing a ecu part number that will run just the ecm? I say this becuase i read i think on here some where that some ecu's would not work with out the traction or transmission system hooked up. I saw in the files that there was a stand alone ecu for the engine and transmision for certain years and models. so we dont car what one we use we jsut want to make sure its going to work of course.

Also as we start to build or instrument panel can some one tel us if the cars all have teh same guages for oil and water or if they use lights? I see the 1uz motor uses a 4cylinder tach so we have that down but we are only going to hook up whats stock in the harness so we need the ohms ratings for the oil and water temps if they are guages and if there lights that is easy enough.

I have all the room in the world on this motor mount. the center line for the crank is 19.5inches from the deck the mount is bolted to. I'm wondering if there are any inexpensive stainless headers out there or does some one have some that wont work for them. If not i'm going to have these manifolds ceramic coated and of course the rest will be in stainless.

One last thing today, the engine covers on the top of the truck motors. big plastic thing cover the whole top of the engine on the later model pick up i saw 5.7 2008 or 2007 tundra. does the 1uz have the same mounting bolts on the engine tops? I know its a stretch i thought i would ask. I need to make a cover and i hoped that since the truck had one i assumed the car would to and i can fabricate the hardware that ataches it if i had to.

thanks Jeff


New Member
There are A LOT of different ECU variations for these engines. I was surprised when I started doing the research. There are a couple threads here in which the members have put together ECU model numbers to try to sort them out. I just remember that people rarely had the same ECU because there are a lot of them and there are multiple variations and those are all different when they come from different countries. At least that is my take on it. I'm not trying to make it sound complicated just giving my thoughts.

Here is the thing... it's just a simple engine! You just need a wiring schematic and the time to study them and study Lextreme.com as well. I would get 1 ECU, 2 harnesses and just strip them down to the bare wires. Then you just have to sit there and do each wire one by one to each component, label all the wires and see what you can do. Then if the thing doesn't fire ask around for a couple people's advice before you buy another one. Or since you found them for $50 just order another one but I would be surprised if you had two of them that wouldn't work.

The wiring schematics are very precise and there isn't any reason you won't be able to get it to work. There is TONS of info around here in which people tell you exactly WHICH wires you need from the ECU to make the engine run. A couple people have put these engines into old crappy trucks with just a basic tools set like you would find at Wal-Mart :) And they do it in like 2 weeks (put me to shame hehe). It's just a matter of doing your homework here on the forum and then rolling up you sleeves and doing the work. You already have a huge head start as you have made friends with the sources for new plugs and you have found a great source for ECU's.


New Member
Well we got the motor over to the hovershop but we couldnt find the bolts at the local hardware store for the engine block to put it on the engine stand. Not a big deal we still are building the composite hull. we got most of the most outer shell of the cabin built now and have decided that with the xtra increase in engine wiegt from the f23 honda we were giing to use at first that will need to add a bit more lenght to the craft so that we have the proper flotation to make it set lvel in the water when its parked. were getiing lots of interest in the motor too. its hard to belive this is old technology? compared with the vw a nd subaru motors we have been using this is like a space shuttle engine to the project.

jeff www.sevtecexplorer.com