Cool!!! So your running Danymax write up ?, all the settings needed are in there i beleive.


No problem man! That's what i do! Its understandable to be surprised with my harness when all you had seen what that other harness. Black wire sure blends in a lot better then some bright colors! Yeah the wire is very important, i use a similar wire, right on with the same size as the factory ECU harness.


Wow that exact issue happened, imagine how often it happens! I sure would hate to spend that money only to have a wire literally break off. I'm sorry that happened to you, the good thin is you don't have to worry about that again! If one of the very important signal wires break then the car will not even run!!!! That's just scary! One thing is these grey ecu plugs are VERY particular how they fit into each other, they can be installed one way and not quite connect, then remove and install again and its good to go. The connector design is just one Nissan didn't do too great. But its what we have to work with.


Oh ok, it def is COLD out. Def get some experience with EMU it will be something to value!


Good job with the whole car!

 

Yea followed DandyMax's write up to the tee.

Thanks man!

 

Can we see some pictures of the harness and how it wired up to the OEM ECU? After speaking to Darren, I'm considering using of the Greddy Emanage Ultimate. Give me a few weeks before I pull the trigger.

 

I don't have fried coils but the issue used to be that if you leave your car on ON or ACC for a prolonged time voltage leaks and melts the coils. I think I have revision (G), and no issues.

 

How do I check the revision of my EU? I did have the car in the ON position for a period of time when I was having issues, is there a precaution to prevent this? Especially when tuning the car will have to be in the ON position to make changes to the EU, unless I make them on the laptop, save the file, and then load them to the EU.

 

well it's a problem in the ON position when the car is NOT running, other than that it's fine. The revision is on the circuit board written in parenthesis.

this was prevented by installing the resistors to the inside of the emanage fixed this issue i believe. Dandymax write up p.24. it says its only for CEL but i believe it fixed melted coils too.

 

Well that explains how my coils fried then, the car was in the ON position and wasn't running since it wouldn't start at the time and I was measuring voltages and left it in the ON position. I may have an older circuit board.

I'll check the circuit board and wire in the resistors while I'm at it before I do anything else. I couldn't find anything about the resistors fixing this issue. Thanks for your input!

 

I thought diodes were used instead of resistors.

 

Did you buy the emanage used? Reason I ask is because its been quite a few years since this was an issue requiring the resistors. I don't have any soldered in mine and Ive had my key on plenty of times for tuning.

No, its resistors.

 

Yes I bought it used but the guy I bought it from had just purchased it from some shop in Cali a few months ago. I'll check the revision and just wire in the resistors to save myself the hassle. Anyone know after what revision they got the board right and fixed this issue?

 

By the way these are pics of how the coils looked,







4 of the 6 coils show the symptom in the above pics which looks like they got super hot and burned up. I checked the resistances on them. The two that look normal read 1.5-1.6 kohms, two of the burned ones read 1.6-1.8 kohms, and the last two burned ones read 2.1-2.3 kohms.

The new coils read 1.8kohms for the rear and 1.5kohms for the fronts.

 

Checked my board it is revision D. I switched jumper 13 to open and the fans come on but they did take a while because its cold. Since I'm using the water temp sensor instead of the knock sensor is there a disadvantage to having jumper 13 open now, which is the setting for knock sensor?

 

I thought the knock sensing feature didn't work for our setups?

I also did some searching it from what Ive read the coil pack issues was only for the Emanage blue, thus requiring diodes.
The Ultimate required resistors to eliminate the CEL for 0201 Ignition Signal Circuit

 

Its not hooked up to the knock sensor its hooked up to the Water Temp but since the fans didn't come on I switched the jumper just as it says in DandyMax's Write Up.

 

had to do the same thing

 

Ok cool, I don't see it affecting anything really at all. I doubt I'll even look at water temp or knock signal anyhow. Does doing this make the water temp signal readings wrong?

 

The reason the coils blow is because the ignition drivers on the EU leak small amounts of current and this keeps the transistors in the coils in the "Active Region".

Basically, the coils are supposed to be either driven ON or OFF but they never get completely shut OFF because of the leaky ignition drivers. This causes them to stay partially ON which overheats the transistors. That's what the burnt square is that is bulging out of your coils. If you chipped the burnt plastic away, you will see a transistor under there.

I run diodes in series (forward bias) with the EU ignition wires leading to the coils. The diodes prevent any current from passing through unless the voltage exceeds ~.7.

I believe my EU ignition harness may already have diode in series, so I may actually be running two diodes in series, which means that no current will flow until there is at least 1.4v across them.

Also make sure you upgrade to firmware version 2.20, as this is rumored to correct some coil melting problems.


I do not run the water temp or IAT into the Emanage. The EU actually loads these sensors down and causes some funky stuff to happen. My temp gauge would never read fully warm. The only way I would run these sensors into the EU is if they were buffered.

Just remember that the autotune (AFR Target) feature will NOT work unless you have the coolant temperature sensor hooked up. I got around this by using a resistor voltage divider circuit to produce a constant voltage which could be fed into the EU to "trick" it into thinking that the car was always warm.


Check my old thread out for some tips (credits to Dandymax for the main writeup)
http://forums.maxima.org/all-motor/6...en-review.html

 

Thanks for your input Unklejoe, diodes are mainly for preventing current from flowing in the opposite direction but since the resistance of the wire is small that small leakage current wouldn't cause the .7 volts to exceed past the diode (from your findings) resulting in the leakage current never reaching the coils. Great info here, good to hear it works both theoretically and practically. Thanks!

Where exactly did you put them? I don't want to tear into my pnp harness.

My temp and iat sensors are both already hooked up to the EU, what I'm wondering is with jumper 13 set to OPEN (position for knock sensor) is that going to prevent me from being able to use the Autotune feature?

Also it says in your thread you did still burn a coil while leaving your car in the ON position while putting your seat belt on, if I'm understanding correctly this is not a long period of time. Or was it a long period of time? I see a problem with tuning if I can't leave the car in the ON position to make my adjustments, unless there is an alternative way people are doing it?

 

Exactly.

Here's how I wired the diodes in. If you didn't want to cut into the PNP harness, you could install them in the engine bay, right before each individual coil.




And as far as the coolant temp reading, I'm not sure. Best thing to do would be to test via data logging and see what it shows for "Coolant temp". As long as it is above 40C, autotune should work.

 

I just wanted to add that the first time the coils got burned was before the EU firmware was updated, it was running an older version. I since updated it as soon as I got the EU up and running correctly with the latest firmware and the software to match. Is the newer firmware resolve this issue?

I see in your write up Unklejoe you blame the old firmware for the frying of the coil. Is it safe to say since I updated the firmware now which was outdated at the time the coils were fried that I may have resolved the issue?

 

Before the coils in the bay sounds good but iirc the harness has more then one wire I'm not sure which would be the correct wire to wire into?

 

You'll need a diode for each coil. You could just be sure to not leave the key on for extended periods of time and just skip the whole diode thing though.

Some people have been running EU's for a long time with no diodes without problems.

As far as the new firmware fixing the problem, its only speculation but so far I have not burnt out another coil and it's been over a year and 20k miles.

 

Honestly, I don't know any who are using diodes in the EU, I know some had to use the resistors but with the newer firmware was supposed to fix that.

 

Theory above about the diodes. Its a possible solution and the resistors is only to prevent the CEL which was fixed in the later versions of the firmware. The diodes was an idea that has been working with the EB for a while now since it had many issues of burning coils. Since the resistance of the wire is low and the leakage current is low, they are not enough to cause the .7 volts across the diode needed for it to operate, as long as the diode doesn't operate no current flows.

 

Since I have the new firmware and warranty on the new coils, I'll run without the diodes or resistors for now and hopefully I won't have any issues. Going to get the WB installed this weekend hopefully get a rough N/A tune in. After, I'll reinstall the 440cc injectors and get a rough tune in.

 

Yeah, I understand that I just didn't realize it was an issue with the EU.

 

Car is going back to stock, have a new project with other plans. What's for sale is here for anyone interested in parts http://forums.maxima.org/general-max...s-95-03-a.html

It was good while it lasted, sucks that I didn't get to install the turbo and see what the car can do before this happened. I'm not going to have room for the car so it must go. I'll keep everyone posted on the new project and I'm predicting when most of you see it, you'll understand

 

You must've gotten a GTR.

 

Yea right

Nope, a Z32 TT

 

I guess this makes it ok that you are abandoning your project. lol.

 

I saw a GTR in town today. GL I heard those things make good power on stock internals too.

 

Good luck hope you never have to replace anything

 

Werd. I worked on 3 different 300ZX. They are a FEMALE DOG! Good luck.

 

Well I wish I could keep both projects but that is not feasible by any means right now, so I had to choose one.

Thanks.

That's why its a project Thanks.

 

Were the injectors the problem?