2012 Infiniti M56 - Timing Retarded, Engine Bogging on Decel, STFT High *FIXEDED

Car:
2012 Infiniti M56
5.6: V8 Direct Injection Gas engine, 60k miles. Always ran on 91 octane. 

My low fuel pressure tests within spec (Line pressure from low pressure pump)
My high fuel pressure is out of spec and does not follow the ECU commanded pressure or the voltage outputs in the service manual(Fuel Rail Pressure from High Pressure Fuel Pump)
ST Fuel Trims are +25, Long Term Fuel Trims are +25
Ignition timing is retarded by about 6-7° at idle.  
And my intake cam timing advances to MAX at idle. 
I also suspect fuel that I have large amounts of fuel in my crankcase as evident by an oil level that doesn't decrease. It appears to either have stayed the same during a weekly check or increased over that same period. 
The only codes I've ever had were a one time P0420 and x3 P0300 - no other codes

Basically the car has been pouring out gas fumes from the exhaust and having jarring timing retard whenever I decelerate or take my foot off the pedal to coast. Car once had loads of power, now doesn't have any torque or "get up".


Pic #1 Below is a log showing this happening.  Timing jumps to -7° and AFR skyrockets. At first I thought this was off, but this is normal. Keep in mind, the first pic is with a larger aftermarket exhaust and no cats.  I was supposed to get tuned, but had to postpone to figure out these issues.

Pic #2 shows what happens to my fuel pressures at the same time - this isn't the same log from above, but this is consistent in all my logs.  My command fuel pressure goes down to about 4MPa but if you look at my actual fuel pressure, it has an inverse exponential increase in fuel pressure.  

I ordered a new high pressure fuel pump, but I am still not convinced that this is the issue, but these typically go bad early.  I haven't checked fuel injectors, fuel damper or ignition coils.  Any thoughts on how this can be connected? Any suggestions?

*Comment Deleted*

Thread updated with newly found graphs.

Hmm, I wonder what a known good looks like, since it does have some correlation with RPM. Do you know what the injectors are doing at that time if you look at their pulse width? I would imagine they shut off during decel. Thinking on the keyboard, and out loud to myself, could it have something to do with decel and the returnless high pressure system?

Unfortunately I haven't found anyone willing to allow me to scan their vehicle. There's only one that I know of within an hour of me, but he hasn't been of much help.

As for the fuel system, I'm leaning towards the issue being between the high pressure pump and the injectors.  My scanner only shows bank 1 & 2 injector pulse width.  My base injection timing low threshold is 2ms and my high is 3.6ms - I am not sure if that is just for idle.  During a random log, I have seen my injection pulse go down to 1.11ms and up to 2.5ms.  To be honest, I do not have a good understanding of how the pressure relates to the pulse width.

Here are two snippets from the service manual on how this particular high pressure system works...

My 2011 m56s I just bought with 60k on it is doing the same thing u describe to a tee! Please let me know if you find what the issue is as this is Starting to get bad!  I am familiar with basic diagnostic readers and even have a few myself but nothing that maps out graph charts so I'm lost. please help me troubleshoot this problem ... It is seriously bad. Feel free to email me at mariasmailbox@gmail.com with any feedback. Any help I can get would b greatly appreciated! 

wrote:

My 2011 m56s I just bought with 60k on it is doing the same thing u describe to a tee! Please let me know if you find what the issue is as this is Starting to get bad!  I am familiar with basic diagnostic readers and even have a few myself but nothing that maps out graph charts so I'm lost. please help me troubleshoot this problem ... It is seriously bad. Feel free to email me at mariasmailbox@gmail.com with any feedback. Any help I can get would b greatly appreciated! 

Maria, the majority of the time these issues are caused by the High Pressure Fuel Pump on the engine or the small bucket that sits underneath the pump that is driven by the camshaft. The engine burns a lot of oil and if not topped up regularly it'll starve that little bucket and you will get low fuel pressure. Usually a P0087 code. If these aren't fixed it can mean catastrophic damage to your engine - I've seen it happen quite a bit. 

In my case I suspect the pump is bad or I have something wrong with the pump solenoid that controls the fuel flow.  I have a new pump on the way next week, hopefully I'll know more then.  In your case, I would get a good scan done, I use a bluetooth scanner with a phone app and a Nissan scanner on my computer, they both show the dealer level stuff, but I they don't have all the testing functions.

If you're on facebook, join the group called "Infiniti M35 M45 M37 M56 Q70 Fuga Enthusiasts Group" - This is where most of the discussions on these cars are and the folks in there are pretty decent people. You can also check  NICO Club

Thank u so much for your help on this I will be running scan tomorrow and see what I can find out for the problem on mine . Good luck to u I will keep u posted on how things turn out! 

So I believe I have fixed the problem, my high pressure fuel pump was indeed malfunctioning. Looks like it was dumping fuel in my oil like I assumed. Installed the new one today and went for a test and the major drivability issues are gone. Hopefully once I flush the oil a few times, it'll be back to newish.