2761 Increased Emissions Sanity Check

[daitheflu20]

I've been trying to diagnose code 2761: VANOS maximum limit position, intake bank 2 for a couple months now.
So far I've swapped intake solenoids between banks and thoroughly cleaned both check valves. I've also swapped the cam position sensors between banks, changed the oil and made sure the gasket is good at the end of the oil cap cage.
I think I've done all the easy troubleshooting but I was hoping you guys could double check my work before I peel off a valve cover and spend real money replacing the intake VANOS adjuster.
When I first troubleshooted in ISTA, my limit positions for intake bank 2 were 126.7 for maximum and 78.6 for minimum. I interpreted the minimum as just outside the permissible. So I started swapping sensors and solenoids.


The most recent VANOS system tests from last night now show the maximum value also falling just outside spec. Intake bank 2 limit positions now returned a maximum of 136.1 and a minimum of 78.3. So now both values are outside permissible range but still same intake bank 2.

From what I've researched, my adjustment times arent exactly great either (and getting worse) but the car isnt complaining about these, yet.

Its a 2010 with 95k miles. I've had it for about 4 years and put about 10k miles on it without any engine troubles. I do think the car had a hard life prior to me. I have no service history but through a VIN check, I found that a mechanic shop in Texas owned the car and when I went down that rabbit hole I found pictures of a car that matches mine perfectly with its engine dropped and disassembled all the way down to replace the crank.

The car drives fine to me. I havent spent much time high in the RPMs because of this issue but it idles fine.

Thoughts? Prayers?

[charliev68]

I would first have your timing checked. Did anyone ever touch your cam phasers?

[omgzirra_exe]

VANOS issues are honestly hard to pin down.

At this point, it’s tough to say whether you’re dealing with a bad solenoid or a VANOS adjuster issue. Based on the symptoms, it does sound more like the adjusters could be responding slowly, possibly due to debris or contamination inside them.

VANOS adjuster failures aren’t very common on the S65, unlike the S85 where it’s almost expected. That said, it’s still possible.

The easier and more logical first step would be to replace the VANOS solenoids. Easy to swap, and don’t require pulling valve covers. If that doesn’t improve things, then it’s worth looking into the adjusters themselves.

[RocketyMan]

OP.
So swapping all your component from left to right bank confirm the electrical integrity of the solenoids and cam sensors I think.

You said you cleaned the check valves. Maybe try doing a fresh oil change? Perhaps there's still some sort of blockage preventing the proper pressures to the VANOS?

[daitheflu20]

Thanks for the ideas guys.
Nobody has touched the adjusters in the 4 years I've had the car but I'm nearly positive that this engine has been rebuilt due to bearing failure in the past.
I've ordered an intake solenoid so I should have results from this closer to the weekend.
I did try an oil change recently. I suppose I could try another but honestly I'm skeptical that a second oil change will have an affect.
When I had the solenoids and check valves out, I tried to clean any passages I could access with small pipe cleaners. I never found anything but clean oil. Any thoughts on hitting these with some compressed air?
I'm leaning towards a rebuilt intake adjuster from Mporium.

[daitheflu20]

Just a follow up incase anyone else runs into this.
Changing the intake VANOS adjuster seems to have fixed the issue for me. I ordered a rebuilt unit from Mporium and swapped it in about 2 weeks ago. I've put about 200 miles on the car since then without issue and my limit positions in ISTA are back within spec.

Swapping adjusters wasn't terrible. I had hoped that I would only need to remove the intake adjuster and leave the exhaust alone but this wasnt possible. There is no way get enough slack in the timing chain to remove the intake adjuster without first removing the exhaust adjuster. Its a good time to replaced the little o-ring (11367839292) behind the adjusters anyways. Rebuilt adjuster from Mporium comes with a new one. The bolts that hold the adjusters on are one-time use. They stretch during the torque sequence. Luckily these bolts are only ~$25 each but if you're doing this, go ahead and order 2.


Original bolt on left. New bolt on right. The gap seen at the top is the amount of stretch.

I also replaced the tensioner while I was in there but the original seemed fine.
I used a timing set from Amazon that cost less than $100. Worked great.

[RocketyMan]

Thank you for reporting back!