VQ35DE breaking up at high RPM

[Delmus]

Ever since I've installed my Link G4+ ECU (PnP) on my 350z I've been unable to rev past 5k RPMs. After doing some logging I noticed that my dwell time spikes down once I reach this RPM range but I can't really explain why. The RPMs also seem to shoot all over the place.. rising as much as +1,000 in one log tick.

 

This car ran perfectly fine prior to the ECU swap but just to cover all grounds I replaced the crankshaft position sensor only to find that it got worse and now occurs at 4.5k down from 5k..

 

Here we can see dwell time spiking down when I reach 4.5k RPMs. 

 

 

I did a triggerscope and everything looks relatively normal except these weird fat spikes. Are these normal for VQ35DEs?

 

I've calibrated the trigger 1 offset using a timing light with no change in behavior.

 

I also see Trig1 Err Counter go up every time I reach this RPM range.

 

Does anyone have any idea if that trigger scope is healthy or what could be going on here?

[Adamw]

The spikes in dwell are where there is a trigger error (ecu has received a signal it didn’t expect) so it has lost engine position.  

Was your trigger scope taken at the rpm that it misfires at?  Those wider teeth aren’t normal although it looks like the falling edge that the ecu uses is still ok in this particular capture.

I would have jumped at it being a dying crank sensor first if you hadn’t said you had changed it already.  Does it have an aftermarket flywheel? I’ve seen those cause trigger issues on vq35’s a couple of times in the past.  

[Delmus]

2 hours ago, Adamw said:

The spikes in dwell are where there is a trigger error (ecu has received a signal it didn’t expect) so it has lost engine position.  

Was your trigger scope taken at the rpm that it misfires at?  Those wider teeth aren’t normal although it looks like the falling edge that the ecu uses is still ok in this particular capture.

I would have jumped at it being a dying crank sensor first if you hadn’t said you had changed it already.  Does it have an aftermarket flywheel? I’ve seen those cause trigger issues on vq35’s a couple of times in the past.  

 

To my knowledge this is the OEM flywheel with probably 130k miles on it.

 

I took trigger scopes at idle, 3k, and bouncing in the breakup area and it appeared to be the same in every case. Since it's always every third set I'm starting to think it may be something with the flywheel. This idea is reinforced by the fact that there's what appears to be damage on the timing ring (how lol?)

 

 

I'm going to go ahead and replace the flywheel with a quality (JWT) aftermarket flywheel this weekend and pray this fixes it. Assuming this is the problem I guess the stock ECU's code isn't as sensitive to small variations as the Link ECU is.

 

Thanks for your reply!