I have been going to post this topic for a while - it's a good one.
I haven't set up a factory ECU in a boat but from my Autronic experience, these are a few issues you will need to deal with.
I run an Autronic SMC Marine version which is fully waterproof. You can chuck it in a bucket of water with the engine running and it wont stop.
Factory ECU's are much cheaper and you get perfect tuning for normal engine running and economy, plus faultless starts. All still possible with aftermarket, but can require a lot of tuning hours!
Factory ECU is also suitable for forced induction, which is nearly essential on larger or fast boats. Not sure how much boost the factory ECU can support.
O2 exhaust gas sensors don't like water. Full stop.
I believe some versions of the ECU use 4 sensors and some use 2.I'm not sure if the factory ECU can be run without them? Rod or KDog would know??
If you are injecting water into your exhausts to cool them and quiten the engine exhaust note, you will run into problems. The o2 sensors have a ceramic part in them and once they are hot, any water that gets on them will crack the ceramic bit and the sensor will be stuffed. I have seen water injected downstream of the sensor to try to get away from this problem, but with limited success. Sometimes when you pull up in a hurry - (fallen skier ect.) water will rush past your exhaust flaps and run up your pipes. Also a coughing or backfiring engine can do weird things and suck injected water the wrong way. You can also run dry pipes in a race boat to get around this. Personally, o2 sensors are for economy reasons and you don't need to run them in a boat. I bolt on a dry pipe for tuning and put a o2 sensor in that, then remove it once I have finished tuning.
Next issue is keeping everthing simple. With the factory ECU you will need to plumb the Mass air flow sensor (MAF) in front of the throttle body. This takes up room under a tight fitting engine cowl. Aftermarket you just run on manifold pressure which you don't need a MAF.
Not sure how many other things are necessary to run the factory ECU wich would clutter up your engine bay. Also remember that every less piece of wiring or electronic sensors or connectors is one less thing for water to get into and give you a great day rowing home. From memory, my Autronic runs 16 general sensor / output wires and 9 injector wires.
It connects to water temp sensor, 1 cam sensor, crank sensor, interface box, 2 ignitors and the injectors. Probably as simple as it gets except for the interface which is necessary.
In conclusion I felt the Autronic was practicle and good value at the time and I am happy with it.
On the other hand, there is a lot known about the setting up of the factory ECU's nowdays and if they can be made to work, you cant beat them for value and engine smoothness ect.
Look forward to replies for solutions to fitting the factory ECU, escecially the o2 sensor issue.
Hey guys Ive heard the 1UZ ECU only needs the O2 sensors and goes into closed loop mode when on constant cruise mode for ecomony (ie highway driving in a car) Otherwise the fuel maps for normal acceleration are sufficient and the ECU is in open loop mode 99% of the time. Is this true?
o2 sensors sort of stop working after 2 or 3 grand rpm
unless u get a very late model 1uz say around 98 or 2000 or newer they might have 4 o2 sensors
or if its an engine from the usa it might have an o2 sensors
i have wired up 60 plus 1uzs and never had one with 4 o2 sensors
personally if u want to go boost then go for aftermarket ecu
u can only run low boost on std ecu and for money and time wasted trying to set up std ecu on boost and gettin to be perfect i would rather save abit more and fit aftermarket thats my opinion others will say std is ok but y not just do it prperly from the start and if u have programmable ecu at the start then u can just retune it easily when u do mods
yes aftermarket is the way to go definatley esp when boosting. the fuels maps need to be spot on for boost ovet 8psi. Over or underfuelling is equally detrimental.
My application is a 1UZ to mercruiser sterndrive, so at this stage I want to do as cheaply and efficiently as possible.
I have wired many 1uz's with standard and aftermarket management in cars and 4x4 and they go well.
We did a 26/22/16/34 pin ecu into a 16 foot jetboat running a Hamilton unit. This engine ran a pair of 4 wire oxygen sensors. The standard loom was bulky even after i removed the trans and traction control wiring.
The owner was going to run a dry exhaust but brought marine manifolds which did not have the oxygen sensor fittings.
The boat started well but the constant load of the jet unit was a bit much for the idle control. It performed well for around 10 minutes then lost power. removal of the battery netted good power for a little while. It through several codes including oxygen sensor heater ( early 1UZ don't have heaters which may be better) and some others which I don't remember.
To sort it in the end I tricked the ECU to add a bit more fuel and it sorted it awesomely. It runs really well and the owner gets awesome fuel economy. He has a much power a his old 350 chev with better acceleration.
Aftermarket management would have been simplier and much tidier. It normally allows a bit more power.
I have done other engines with standard management into jetboats with reasonable success but generally get better results with aftermarket. Tuning boats result in very different maps to when I do cars.
So my advice is that it standard management can be made to work but aftermarket is easier to work with and normally gives better results - cheers
Ok so what setup are we talking here and what are the costs?
Can I buy an aftermarket ECU with loom with a preinstalled map which will plug straight onto the engine...also what manifolds should I have ...should I go for ones which can have an O2 sensor, or would you just delete them running open loop fuel mode in the ecu all the time?