Nandosan I suspect that tensioner theory might not be the direction to follow.

I used VQ35DE cam tensioner plungers in my VHR being that they are a direct fit and replacing the actual cam tensioners require the VVEL cam ladder assembly to be removed which is a job you truly dont want to do. I replaced my tensioner plungers because the shoe guides were worn and for $30 it doesnt get better. I never had a problem after this and this actually cured my chain rattle upon a dry start.

What I suspect that's happening to you is debris inside of the VTC not making it cooperate. It's quite possible that your phaser rings have shifted which cause the cam to not be in the correct position as the VTC starts to operate. I suspect that this rattle could be the VTC rattling as the ECM reads the position and sends the command, the cam is elsewhere in reality but the ECM recognizes the actual position after the ring reading. So this causes a slight retard then a correction, then retard to try to give the desired angle. Over many times the code will be set from the engine not obtaining the angle it commands.

Anyways I try to encourage folks to document your actual VTC phaser rings.

I believe the R VTC ring tooth should be between tooth 5-6
L VTC ring tooth should be pointing towards tooth 8

JWT has a picture of them shifted but dont offer a way to actually determine reference point like I have. Finding the average of where that tooth should be in relations to the gear's teeth is what we need.
Unfortunetly I dont have a brand new L VTC to determine the most correct of position.

 

im going to post a vid on my YouTube and send you the link to show you the amount of slack the VTC phaser has from the loose tensioner. That tensioner has enough slack on the chain to create a timing issue between the phaser and the exhaust. When the solenoid fails, the built in one way valve in the tensioner cooks. Ima gamble it and leave the original phasers on my car and send the the tensioner swap and see how that goes for me.


As per the cam phasers. The Right Phaser (driver side) shows that the dowel closest to the timing mark should be between the 7th and 8th tooth on the new phaser, this shows the same on the original one off my car.
The Left Phaser (passenger side) shows the dowel closest to the mark being exactly five teeth away. This correlated with the new one as well.

 

 

Thank you for those pictures and video.

So additional info that could possibly explain certain things:

In a conventional motor that slack would be something to pay attention to, you would place bank 1 on TDC which you are on Bank 1 and check.
You would then move bank 2 into TDC on cyl #2 which you are not (because you are TDC on 1) and it should be the same slack. If it's not then it would require more diag.

Now on a VHR while the engine is off the Actual intake cam will not push down on the valves being that the eccentric shaft of VVEL is retarded not letting the valves open.
So it's quite possible that bank 2 not being at TDC and engine being off so VVEL is not pushing on the valves will give you more play.

If you have the new phasers go ahead and throw them in there.

 

it’s not so much the slack of the VVEL system itself but of the lack of tension the chain itself should have from the tensioner. When putting bank 2 on TDC and checking the slack on the exhaust cam chain on bank 1, the tensioner is solid and the cam phaser does not rotate without the exhaust cam. When TDC on bank 1, the bank 2 tensioner has failed and this allows the cam phaser to rotate a few degrees back and forth before the chain itself tenses and the exhaust cam follows. Same goes if I do bank 1 TDC and check bank 1 tension and bank 2 TDC and bank 2 tension.

The issue I’m worried about now is having to remove the VVEL ladder assembly and taking off the actuator subassembly. Resetting the actuator looks extremely tedious lol

 

That is how I did my M3 club car when retiming it for an electromotive back in '02. I used a welding rod.

 

I did not check my cam chain tension at all but should have.

 

I have no idea WHAT the issue is here...I do not know, since my engine is not apart, what I am looking at Bank 1 vs B2. old vs new. WTH is going on here...?

 

This may also be a good reference for slipped ring:
http://www.jimwolftechnology.com/wol...derslipped.pdf

 

Thanks! Phaser = encoder?

 

Those are the VTC timing wheel, It lets the cam sensors know the position of the VTC gear. If you see the first pic I posted, is a comparison between an old gear vs new. Old gear had a p0011.
This was on a 2013 Z, gallery gasket was not terrible but had broken, ring had shifted. So a gallery gasket would not had fixed the issue.

This ring on the phaser can shift from lack of oil, it overheats and then shifts into a retarded position being that they are heat pressed into the gear. The pictures are to serve as a guide so you can count where the tooth on the wheel is in relations to the dot of the gear.
Looks like R VTC should be between tooth 5-6 and L VTC should be on tooth 8. If it's not then the ring has shifted and VTC will need to be changed. This is yet another possibility for the p0011 & p0021 code.

@Nandosan So in my inspection of the cam tensioners, the tensioner body which lies in between the VVEL ladder assembly is just an aluminum body that channels oil pressure into a chamber that pushes the plunger. All of the action is done by the tensioner plunger.
In reality these are free-floating tensioners with no lock unlike the main chain tensioner. If you are indeed having a failure there it should be the spring inside. I'm 90% sure there is nothing wrong with the body of the tensioner which means it does not need to be changed.
Now a failure point could be a weak spring or that the shoe on the tensioner has worn like my old ones.
If they have I'd suggest you buy yourself a DE tensioner set and steal the plungers from it and replace just the plungers on the VHR tensioners, this way you avoid 5 hours of work and possibility of messing things up further down.

Post #40
https://www.myg37.com/forums/build-t...edition-3.html

 

HR and VHRs use this design of tensioner on the exhaust cam chain as demonstrated in the YouTube vid. It doesn’t have a ratcheting system like the main tensioner. The upper tensioners use the oil as a hydraulic system and a one way style valve system. When these fail on our engines and the chain gets loose, it won’t skip a tooth because even without a tensioner, the chain is too small and confined under the phaser, but it’ll cause enough slack and very possibly some timing issues if both cams are moving at the same time/delaying from the loose chain. It could also explain my nasty *** rattle. If you Google “bad tensioner symptoms” and then google bad can phase symptoms, they have almost the exact same symptoms lol


if you watch the video I linked on this comment and then compare it to the video I posted of my tensioners, it correlates

THIS COULD ALSO be why when we hit 3500rpm or higher, it doesn’t act up as much because once 70+ psi goes through the tensioners hydraulic style system, the pressure outweighs the loss and the chain gets somewhat tensioned, but at lower RPMS and sub 60psi the pressure is less than the loss. It won’t rattle at idle because the engine isn’t outputting any force or torque but the moment it’s in gear it will.

Since my phasers look identical to the new ones, I will gamble it for the sake of proving myself wrong or right and hopefully maybe find an answer to many people’s rattle and/or persistent infamous codes

 

Thanks guys. I just got off the phone with a local Nissan guy and was told that, yes, even the cheap VVT solenoids have bitten them before and to get a real OEM Hitachi. I will test the one I installed but going to throw another $96 at this.

 

I have noticed a difference between the rattle that the video shows and I can agree is the same rattle that I have. Now I have heard the secondary timing chain rattle usually from workout shoes on the plunger and it's one with a higher count rattling noise than the one in the video.

The secondary tensioner BODY does not fail/has any failure points. You could in theory have a separated bottom plate of the tensioner leaking oil pressure however this is unlikely being that they are machined flat surfaces and riveted pin holds it in place, lastly held down by two 10mm bolts torqued at about 15-18 ftlbs. This convinces me that the body of the tensioner has low percentage of failure. This leaves the plunger. Comparing my old plungers to new ones Im able to say that wall thickness of the plungers changes very minimally as far as wear goes. My new plungers slid perfectly into the body of the old tensioners and since 30k miles has never given me an issue. I noticed chain rattle upon start up disappeared when I replaced them and I do not get any chain noise on a dry start. My typical rattle is after engine coolant warm up 165F.






In the log you can see how while this event is happening, analog oil pressure fluctuates 20psi +/- similar to an EKG while having a heart attack during this rattle. VTC angles will show bank 2 acting normal and bank 1 at 0, 10, 20, 30 degrees and back and forth until 3k rpm then suddenly match each other like they should. While all of this is happening IVT solenoid readings are the same. This tells me my solenoid are good and that the issue is post solenoid. Being that B1 sees oil before B2 If im having pressure issues B2 should be suffering as well which doesnt happen. Per oil psi gauge I have plenty of pressure.

This lastly lead me to believe that rattle is possibly VTC cover and or VTC gear- The cylinder built into the cover with the rings is receiving oil pressure but there is too much clearance between the ID of the GEAR and OD of the VTC cylinder causing an internal leak. This could make sense why 3krpm makes it work correctly being that at that RPM im at 50+ psi. The video @m3clubracer posted about Seth talks about this specific rattle being attributed to that.

I would like to do more research on the VTC cover failures to see if he's right. In theory he is and gave me something to think about.

 

@BULL Wow, how many miles are on yours? What oil do you use? Man, at 251k I might need all new tensioners on the cams. I wish I had checked my tension (like Nandosan) and guides. What is the PN for that tensioner?