ShipFixer wrote:On the road trip just before my repair, the best I could get was 18.5mpg. Just drove to Middleburg and back and saw 19.5.....

'Bout what I get on the highway unencumbered. I have found that the MPG calculation by the vehicle display can be almost 1 MPG off (either way) compared to calculating the MPG manually.

One code today - P0011. Let's just hope this one is electrical and not a chain install issue! Truck is running fine, so I am going to try to check the sensors and contacts. Since I got a pile of unrelated codes at the same time on Saturday, I think the odds are good.

Mine threw a P0011 code after the timing chain install and it was because the epoxy gasket didn't seal the entire way around the front cover. The whole job had to be almost completely redone.

docwatson wrote:Mine threw a P0011 code after the timing chain install and it was because the epoxy gasket didn't seal the entire way around the front cover. The whole job had to be almost completely redone.

Was that leaks/oil pressure? I have leaky valve covers and some other things I'm gonna fix. Getting a scanner that (cross fingers) can see cam phasing and gonna tackle some possible electrical grounds in other sensors like the VVT solenoid.

Will check the the front cover and see if it's still sealed though - thanks! I can see the top is cleaner since they sealed it but haven't looked at the bottom.

I don't have any other indication of bad cam timing. Truck pulls to redline just fine, no hiccups. (This is me, hoping for the best!)

ShipFixer wrote: Was that leaks/oil pressure? I have leaky valve covers and some other things I'm gonna fix. Getting a scanner that (cross fingers) can see cam phasing and gonna tackle some possible electrical grounds in other sensors like the VVT solenoid.

Will check the the front cover and see if it's still sealed though - thanks! I can see the top is cleaner since they sealed it but haven't looked at the bottom.

I don't have any other indication of bad cam timing. Truck pulls to redline just fine, no hiccups. (This is me, hoping for the best!)

I swapped a VVT solenoid thinking that was it but it kept coming back. I fixed my valve cover leaks when I had it all apart. And similar it sounded great and there was no indication of any issues.

I ended up taking it to the dealer to diagnose. They said it was an issue with the seals on the front cover. I may have misstated the issue earlier. I think I pinched one of the o-rings when I was closing it back up so they had to pull it apart for just that piece.

docwatson wrote: I ended up taking it to the dealer to diagnose. They said it was an issue with the seals on the front cover. I may have misstated the issue earlier. I think I pinched one of the o-rings when I was closing it back up so they had to pull it apart for just that piece.

Think I found that explanation on a few of the forums. There's an o-ring or something that can block oil flow through the camshaft sprocket and prevent VVT actuation. Was that it?

Some updates. I was able to use an ELM327 bluetooth OBD II reader and Nissan DataScan II for Android (reverse engineered CONSULT II reader) to read engine ECM data on my phone. I can see both the VVT solenoid signal and camshaft phase (position sensor) data in real time now. At idle, both sides sit around zero degrees advance (FSM says +/- five degrees). At 2,000 RPM, one side advances and the other sits between zero and four (FSM says 0-30 degrees). Driving to work today, bank 2 moves freely between zero and forty degrees while bank 1 mostly sits there.

In the FSM it could still be mechanical timing or another VVT issue inside the camshaft, but now I'm at least a little hopeful it's the solenoid or a sensor.

Screen shots:

I'll figure out the hosting later - suffice to say it's pretty nice to see the data!

Into the solenoids now...good news/bad news they look pretty clean, the gaskets weren't even leaky. Voltage test next. Don't like the other possible root causes!

Aaaaand it's not the solenoids or their control signal...

Passport Nissan found the problem. Same thing as docwatson: the dealership that did the previous repair replaced the front timing cover seals with rubber O rings instead of the OEM parts with different material. (Passport did not remove the covers from the front cover.) I'm waiting on them to get new timing covers for a permanent fix, but with a temp fix in place both of my camshafts are advancing as ordered by the ECU in Nissan DataScan.

Just raced a Tahoe up the hill when it tried to cut me off. Engine does pull a little smoother and better now that the intake is doing what it's supposed to when you're on the gas! B-)

I kept my fingers crosses all along.. Glad they found it out..
Again we have a dealer Experience forum to hand out Kudos (or complaints if u can remember the name of original dealer)

viewforum.php?f=18

Sorry I get back sooner but I am glad its fixed.

I love the sound of the VQ40 with fixed timing chains.

Ok, here’s what I saw in Nissan DataScan II. The dealership saw the same data in CONSULT II.

Here is the engine warm at idle, no voltage applied to the solenoid and cams are sitting in phase (zero degrees offset ordered, varied +/- two degrees) with mechanical timing:



FSM test says at 2,000 RPM, you should see the cams advance between zero and thirty degrees. Here I saw one cam moving freely:



(Yes, the solenoid voltage appears to be “b1†twice...it’s really b1 and b2, a typo in the app. The data displayed fluctuates between the two in real time.)

I’ve still got to go back and get the right timing chain covers with the correct seals installed by Nissan, but since they moved the failed O-ring out of the way now I see both cams advancing freely, roughly in time with each other.

Wish I could find the thread, but elsewhere I did see where someone had installed their cam chains a tooth or two off (might not have been on a VQ40DE, but a Maxima or something) and were able to see the timing was not 0/0 in Nissan DataScan.

A side note here - last month during my 2,000 mile round trip I got a P0430 (right bank or bank one catalyst efficiency warning) in the middle of it at my parents. I changed my spark plugs the next day at ~80K miles out of 100K mile lifespan and the code has yet to come back. But one of the plugs in bank one was half eroded. Figured it was an oddity as I didn’t have anything in bank one to tie it to at the time.

Since my engine is now running a bit smoother than before and there’s no way of knowing when that o-ring failed (maybe from the beginning?), I’m thinking this might have been the culprit there. Mystery solved...perhaps

Does the timing chain noise get quieter as the engine warms up? I have a noise which I believe may be the chain (based on reading threads like this one) that is very noticeable at start-up and initial driving, but it seems much quieter after driving for a while.