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No spark on 350Z ECU in G35

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After countless hours of searching the web, and this forum, I have yet to find an answer to my issue, so I am resolved to simply asking the questions here.

A brief backstory...

I picked up a 2005 G35 6MT coupe. The car came with an APS twin turbo kit installed, but I wanted to upgrade to a system I could tune and/or flex fuel. The APS setup is very proprietary, and gives you NO options for upgrading it, or even tuning it to run right if something small is outta whack (hence why I HATE cookie cutter kits). The prior owner spun a bearing in the motor, so he sold it to me.

Upon upgrading everything, I also took out the APS piggyback and installed a Link G4+ plug-in for the 350Z/G35/V35. To my dismay, the engine will not spark now. I have installed a set of brand new OEM spark plugs, but have upgraded Iridiums on the way to better handle combustion under boost. There is a lightweight flywheel installed, but that was there before the car was disassembled as well. Before I pulled the car apart to rebuild the motor, I was able to plug the link into the piggyback unit, set everything to stock settings, and start the car. Once I removed the piggyback and was using only the link, I have not been able to get the motor to start. I have verified that I have functional fuel pressure and injectors are in fact working (fuel smell on the plugs after removing them). Coils have their necessary power and ground, and are within spec. The original APS piggyback had a separate lead that ran all the way to the crank sensor, but I am on the understanding I wouldn't need to do that with the Link installed, so I removed that and am using the original EFI harness.

When I crank the motor over, everything sounds completely normal, but there is no spark. I went into the PCLink software and verified that I do in fact have signal coming from both triggers 1 and 2. I have no errors (an V12 was a high volt error after getting the base map loaded, so I changed the error values to match, but then ultimately just turned it off altogether). From the little I was able to find, I should get the trigger flags to switch from NO to YES when the engine is rotating, but that I should ALSO have the Engine Speed read the current RPM's even while spinning at starter motor speed (aprrox 300rpm). Both trigger flags are good, but no engine speed is registered. Does this indicate that the ECU isn't syncing the ckp and cmp together, and it can't find TDC of cylinder 1? Would that have anything to do with the engine speed not registering? The help info is pretty limited in this area, and the Link distributor that sold me the ECU has apparently screwed over a lot of other customers as well, and is now in jail... so he isn't any help.

What am I missing here? I am pretty sure, once I figure out ignition output, I can fire the motor and tune it just fine. If you have any settings/parameter questions, I can gather any info you like.

On a sidenote... I would like to use the onboard MAP sensor and run a a boost control solenoid output from the ECU. The APS unit ran PWD signal from a remote unit, and power was straight from the battery. I don't care if I have to run a relay to power the solenoid, but how do I wire in the PWD output from the ECU if it uses the OEM harness?

Thanks in advance,

Charles

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Hi Charles,

Yes you should see about 200RPM when cranking.  A couple of quick tests that will help us get to the bottom of your problem quickly:

  1. Please do a PC log of the engine cranking - say just 10 seconds or so will do.  How to set that up: https://www.youtube.com/watch?v=_P1LRANeO4A   Attach a copy of that log and your map here.
  2. Do a triggerscope of the engine cranking.  A quick guide here:  https://1drv.ms/v/s!AiYbYlZQuRHPjDE8OgHfIlphsFpR   Attach a copy of that here.

For the boost solenoid there are a few aux outputs that you may be able to re-assign.  Easiest would probably be aux 6 or aux 7 which were originally used to control the heaters in the narrowband oxygen sensors. - assuming you wont be running narrowband oxy any more?  Aux 6 is on pin 24 and Aux 7 is on pin 2. 

 

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Adam, yer awesome. Thanks for the quick reply. I will do that either tonight, or early tomorrow and get that posted up.

Yes, I will no longer need narrowband sensors, so those outputs are a great idea... I may even install a second solenoid and run a dual setup, using BOTH the outputs. hahaha.

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Now, I realize my batt voltage has dropped a bit, but aside from a slightly reduced rotating speed, everything else is the same. I will work on charging the battery if these logs aren't sufficient.

Also note, I am running Injector Dynamics 1050cc injectors, and I have adjusted accordingly.

Trigger Scope Log 2017-08-16 12;03;30 am.llg

no spark.llg

no start.pclr

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Ok, there is a little bit of weird stuff going on with the triggers.  Your triggerscope shows Trigger one has a few extra "phantom teeth" compared to normal.  Hopefully that may just be due to your flat battery/slow cranking and might fix itself. - otherwise there might be a wiring problem?  Maybe when those separate trigger wires were removed?

Also your Trigger 2 is inverted compared to our expected VQ35 pattern, so try changing trigger 2 edge to rising and see if that helps.

vKyeWsX.png

Edited by Adamw

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Do you have a VQ35DE or a VQ35HR / VHR? As per this thread here http://forums.linkecu.com/index.php?/topic/6374-g4-thunder-dual-dbw-nissan-vq37hr/ the hr engines and the VQ37's run a different cam trigger than the DE's and the signals are inverted

Also, this image here, which is the first google result for VQ35 crank trigger, shows a 5 tooth cam trigger (same as the thread above, but different phasing), whereas your scope looks like it only shows 3 teeth on the cam trigger (and just the cam signal is inverted). Are you sure you're running the stock cams, trigger wheels, pickups, etc? Are you using the intake or exhaust cam for the trigger 2 signal? 

Image result for vq35 crank trigger

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The motor is a VQ35DE RevUp. Exhaust cams have VVT, but only a single throttle body so not an HR motor.

I imported a base map and setup the ecu to enable the exhaust vvt. Calibrated accelerator pedal and throttle plate. I didn't even know I COULD use an exhaust can as a trigger... Figured the defaults would have used the intake? Is there an easy way to determine which cam is being used as the trigger source? 

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Your main problem at the moment like I said earlier is trigger 1 on the crank.  It should look like above with groups of 12-2 teeth, but yours has got a whole lot of weird stuff going on.  Since the engine used to run I would not suspect the sensor yet but possibly wiring related.

tj7etqx.png

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Actually looking at the trigger scope above again I notice they are showing battery voltage whereas our pull up is only 5V.  So, please try turning the pull-ups off both on trig 1 and trig 2 and try another triggerscope.  I suspect either your sensors are different to normal 350Z and have pull-ups built in or possibly they are wired wrong. If turning the ECU pull-ups off doesnt help we will need to look closer at wiring.

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I do know that the flywheel is a lightened aftermarket one. It ran prior with this flywheel and sensor, but that was through an aux shielded wire ran to it from the piggyback unit. The OEM CKP was not being used. Resistance tests show the wires to be ok, but that's not to say I'm not getting EMI noise either.

I did find one slight bend in the ring, but that's fixed to within 0.5mm or so

The rest of the wiring is all OEM. The EFI harness was never cut into, or damaged, and had less than 50k miles on the car. 

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Looks like the flywheel at least uses the same trigger pattern as stock, its 3x groups of 10 teeth, with a gap of 2 teeth between each (so 36-2-2-2). That means the second and fifth groupings of crank teeth in that scope are from the same teeth, and the exact same issues with the waveform are present. It may not be sensor noise and may be some scratches/bad machining/other mechanical problem with those teeth on the flywheel. can you pull the crank sensor out, shine a torch down the hole, and get a helper to slowly turn the crank by hand with a breaker bar? See if you can spot any issue with the first and last teeth on 1 of the groups of 10.

Also, try removing the spark plugs and getting another scope capture just in case those weird patterns are something to do with engine speed slowing down on compression strokes or something like that given you say the battery is low.

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Huh?  Its not even a VQ35 sensor?  It would have been nice to mention that at the start...  So what sensor is it?  

Yes, it is NOW all OEM. The original sensor used was the OEM one, but it had a pigtail ran directlly to it, outside of the OEM EFI harness. The sensor hasn't changed, only the harness going to it. Sorry if I didn't make that part clear enough.

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No you've still got something screwy going on.  Trig 2 looked better when the pull up was on.  Trig 1 maybe looks a little better with pull up off but is still not right.  I dont know if its the sensor or the flywheel or your wiring but it is not going to run like it is.

 

Can you confirm crank sensor wiring matches below.  

Pin 1 "R/W" to +12V.

Pin 2 "W/L" is the signal connected to ECU pin 13

Pin 3 "B" to ground 

yYXthgr.png

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Taken from the manual for the 2005 G35.

Same pin out, different color wires. As soon as I had a no start condition, I verified continuity and voltages right off the bat. Everything checks out electrically. Thinking of soft splicing a harness at both ends of the existing CKP leads, and seeing if the new wiring helps at all. Again, the harness is all OEM, the sensors should also be. I have read that you have to use the piggyback harness from the APS unit when it's plugged in, cuz the CKP sensor won't read from the factory unit (I assume due to the NATS conflict since yer basically bypassing half of the ECU signals thru the piggyback. Upon inspecting the harness from end to end, nothing seems tampered with or damaged. Piggyback unit is removed, and the pink wire on pin 1 has proper voltage. Pin 3 has solid continuity to ground as well.

Screenshot_2017-08-17-00-18-23.png

It may also be pertinent to know... Before the motor came out, I had used the link ECU WITH the APS piggyback, and I was able to start the car just fine. After pulling out the APS crap is when I had the issues. Everything is back to stock now on the wiring, with the exception of the new injector connectors (properly crimped on with the sealed connectors supplied buy Injector Dynamics). 

As you said Adam... My main concern right now it's trigger 1. Without that correct, nothing else matters. I'm going to only focus on that for the time being. Really don't wanna have to pull the trans down, so I'm trying to inspect the ring gear. I bought an aftermarket sensor to test against the OEM one, with the same results.

When looking into the trigger setups... The default for the filter range is 1, but it was already set to 3... Which is odd, cuz I wouldn't have ever changed that. I set it back to 1 (default) for this process. Should I set it back to 3 instead? 

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All I have had time to do since last updates was swap out the battery to a fully charged one. I will get under the car and inspect the ring gear further to see if it is causing my issues. I notice that each of the trigger scopes are showing the same teeth in the interval as being the failing ones. I presume that tells me it is failing at the same point on each revolution... leading my belief to be a bent/damaged ring gear. I will know more tomorrow after I get a few hours of shut eye.

Thanks again for the help. It's greatly appreciated!

fresh battery log.llg

fresh battery.llg

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Well your trigger scope still looks the same but you now have sensible looking RPM numbers being displayed between 24 and 32 seconds into that log where it looks like you're cranking it over. 

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OK, so... I have good cam signal now. Engine speed is showing consistent the entire time I am cranking over the engine. I still have that one tooth giving me a janky signal, but this is as far as I have gotten. Ready to tackle this and get it completed. If ANYTHING else looks strange/off (besides the ring gear tooth, I am working on that), lemme know. I will also be attaching an image here soon of the APS piggyback kit, so I can give more clarification to what USED to be installed.

If I need to, I will head across town and pull the 4 CMP and 1 CKP sensors off my other G35. I know they are all OEM original sensors.

after reassemble scope.llg

after reassembly log.llg

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***EDIT***

Off the wall question.... 

In the help files, the arming voltage of a trigger should be set to half the lowest peak value, correct?? If I am SUPPOSED to be seeing 5v readings, it would be sensible for the arming voltage to be set at the 1.48v (rough estimate from memory)... Tho a little low if aiming for half of 5V, I could see that being relevant. HOWEVER, as it was noted, I am seeing just under 10V on my triggers. Should I be changing my arming voltage to something closer to 4.5V? I am noticing that with or without trigger1 error counter registering errors, I AM showing engine speed now, but I am NOT getting the ECCS sync to flag YES. Is it as simple as my trigger2 is not "arming" the pulse, and syncing the cam to the crank?

or would this only matter in a reluctor type trigger?

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Pics for reference on the APS piggyback. The unit had it's own shielded wire that ran to the crank sensor. The only wires I haven't pulled yet are the ones for the boost control solenoid.

As you can see, the OEM EFI harness is installed straight to the LinkECU with no further modifications. Vacuum line runs thru the firewall to the manifold. Once the car is running, I will mount everything in place as it should be. To point out again... with no settings changes whatsoever, this ECU plugged in to the piggyback, then to the same EFI harness still in use, the car started fine. Nothing has changed in the ways of the cam sensors, crank sensors, or wiring, with the exception of using the OEM wiring for the crank sensor now, instead of the shielded one from the piggyback.

2017-08-22 15.35.46.jpg

2017-08-22 15.36.14.jpg

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***EDIT***

Off the wall question.... 

In the help files, the arming voltage of a trigger should be set to half the lowest peak value, correct?? If I am SUPPOSED to be seeing 5v readings, it would be sensible for the arming voltage to be set at the 1.48v (rough estimate from memory)... Tho a little low if aiming for half of 5V, I could see that being relevant. HOWEVER, as it was noted, I am seeing just under 10V on my triggers. Should I be changing my arming voltage to something closer to 4.5V? I am noticing that with or without trigger1 error counter registering errors, I AM showing engine speed now, but I am NOT getting the ECCS sync to flag YES. Is it as simple as my trigger2 is not "arming" the pulse, and syncing the cam to the crank?

or would this only matter in a reluctor type trigger?

The arming Threshold is only used for reluctor sensors.  The ECCS sync flag is only used for the Nissan 360 opto triggers like RB/SR's etc had.  So neither of these are relevant to your engine.

You've still got trigger errors incrementing quickly due to the odd waveform on trigger 1 so that still needs a closer look at.

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These ECU will fire a car straight away if everthing is all good on the Motor.

We have seen issue with cheap aftermarket sensors that wont give a good signal and the other issue we see is the after market flywheels are under size and the crank triggers are too far away from the sensor this will cause ghost triggers.

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