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Discussion Starter #1
Ok first let me say I am a terrible electrician, all that lingo is not in my vocab. That being said I am a really good mechanic (aircraft mech). So the problem I have is my brothers car. Ive had his 1jz supra 91 for about 3 years. We converted it to a single turbo last year.

Car worked good on start up except it was running a little rough. so my brother took the tune off and loaded a new tune on from driftmotion. Cool except it wont start. He loaded the old tune back on and no start. I changed the injectors and fuel rail recently and added on a fuel pressure regulator.

So what I have done some far and info on the car.

It has an AEM series 2 in it.

I have two ignitor boxes to swap out and they dont help

Ive read out resistance on the cam sensors both got around 1140 ohms cold.
These have been recently replaced.

The crank was 1130 cold but the plug behind the alternator I noticed was partial melted like it had sit up against a turbo manifold.

I have fuel to the cylinders and no leaks.

My only spark plug that is firing is my number one cylinder thats it! All the others are dead. I plugged in that one firing spark plug into another coil to see if it would spark and no dice.

When I am looking at the AEM workspace I can see that number one coil firing off but it shows the other 5 banks dead

So from here i am lost. I am not the greatest when it comes to wiring but I can manage if you talk me through it. I am more of a hydraulic and jet engine mechanic.

Another thing is where can I find the grounds for the intake manifold? I know where the one is by the battery but I cannot find the other ground for the engine.

Also If its something I am not entirely sure what the car has its because I cant ask my brother because he is on deployment but more then likely I know some. I dont own this car but I sure have learned a lot from dealing with it for the past 3 years!
 

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Discussion Starter #2
Also if anyone is in the corpus christi tx area that doesnt mind swinging by and check this car out with me
 

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JZ swapped, I'm guessing. :)

Verify spark and fuel, then move to fuel adjustment.

If you have no spark or fuel, check wires to crank sensor. Sometimes a common ground for all sensors can be the culprit.
 

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Discussion Starter #4
Hello, Thanks for the response! I have fuel and I have spark but only for one cylinder. the only thing I need to check is the wires leading to the crank sensor. this motor has been in the car for 5 years
 

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This might be a dumb question but do you have another ecu you could try as well if the grounds and crank signal wires prove to have no open or shorts? Did the car start running rough directly proceeding the single swap?

Honestly if nothing else was touched except the tune and now you loaded the old tune back with no joy I would atleast try another 1jz base map tune.
 

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Not sure if you have these pinouts and how the ecu was wired or if a patch harness was used but you could atleast ring out the appropriate signal wires if need be.


 

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Discussion Starter #7
So if I want to read out power for #3 ignitor coil from the ecu I would apply my multimeter lead to pin 3 and then ground out and I should get 12v?
 

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Do you have access to an oscilloscope? Those signals are pulse signals and should only fire once the crank sensor tells the ecu it is in the proper degree on crank angle to do so.

You would need someone to crank the engine while you are testing the signal. You could use a multimeter but you should only see a quick deflection in DC voltage.

The connector would still have to connected and you would have to probe the wire through the insulation on the rear of the connector. Yes, one side would have to be to ground if you are using a multimeter.
 

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Discussion Starter #9
I do not have access to that, so just an update, No I dont have an oscilloscope handy. So the one spark I have is a very weak spark its not blue in color and it doesnt fire off consistantly. It fires of almost randomly.

Also I checks the grounds for the engine bay and everything seems intact. Checks the grounds that go from the battery to the fender. the ground opposite of that by the intake. the grounds on the intake manifold and they all seem like they are in order.

Anyone else have any ideas? Are the numbers I got for my reistance for the sensors correct?
 

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I can't attach the chapter out of the TSRM for 2JZ-GTE ignition because the file size is to large. While not everything is the same the resistance values for the cam/crank position sensor I believe are (the resistance values of those sensors you took readings on look in tolerance). Also the methods in the manual on how to go about testing your current issue will help because the method doesn't change. You can download the MKIV TSRM as an app in the play Store or there is a link in the forum if your search for it.

The 1jz manual is all Japanese that has been translated and many things didn't change when it came to resistance values for sensors on the 2jz.
 

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Discussion Starter #11
Ok sorry for the last response, figured it out. Read out wires found that everything leads back to a bad ECU, the ECU in it is a new AEM series 2 it worked fine the first few times. Anyways looked around and noticed the old ecu was still in the back of the car plugged it in and it fires right up. So i am assuming the AEM ECU is fried or it needs a tune since it wont fire off the other 5 cylinders for some crazy reason
 
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