2.7T - camshaft adjustment and phase (blocks 090-093)

[vtraudt]

I still trying to comprehend the meaning of the values in block 90-93.
Example:
block 90/3: 0 Adjustment bank 1
block 90/4: 0 Adjustment bank 2
but
block 93/3: -8 Phase position bank 1
block 93/4: 0 Phase position bank 2

What are the specifications/range for adjustment angle and phase?

[vtraudt]

Decided to do a timing belt service now instead of later.
Cam sprockets and crank TDC perfect.
But block 093/3 and 093/4 still show -5 and plus 2 (was -8 and zero).
I did NOT verify cam chain.

With cam sprocket (exhaust cam) dead on, and blocks 90/91/92 showing zero or +/- 1, does the -8/0 or now -5/2 mean that bank 1 cam chain is off by 1 link?
Is the phase spread (of 7 or 8 total) indicative of a chain link?

Or is the cam chain tensioner on bank one not tensioning the chain enough? (no obviouss chain clatter noticeable though).

The ECU only has crank position (very precise) and intake cam position (one impulse per revolution).

Still not clear what the values block 90-93 really MEAN and where the measurements are coming from (or are some calculated?)?

[Osmosis]

Decided to do a timing belt service now instead of later.
Cam sprockets and crank TDC perfect.
But block 093/3 and 093/4 still show -5 and plus 2 (was -8 and zero).
I did NOT verify cam chain.

With cam sprocket (exhaust cam) dead on, and blocks 90/91/92 showing zero or +/- 1, does the -8/0 or now -5/2 mean that bank 1 cam chain is off by 1 link?
Is the phase spread (of 7 or 8 total) indicative of a chain link?

Or is the cam chain tensioner on bank one not tensioning the chain enough? (no obviouss chain clatter noticeable though).

The ECU only has crank position (very precise) and intake cam position (one impulse per revolution).

Still not clear what the values block 90-93 really MEAN and where the measurements are coming from (or are some calculated?)?

I'm not sure what you are referring to when you talk about sprocket (exhaust cam) dead on, and blocks 90/91/92 showing zero or +/- 1, does the -8/0 or now -5/2. I would verify by the firing order starting from cylinder no. 1 is @ TDC and then throughout the firing order. Guess to do this right, you need to put a dial indicator on the intake valve/cam, crap, not sure on OHC cars :( and then watch the crank position. I guess you could get a sturdy rod and put it into the spark plug hole and measure the rise with a dial indicator to find TDC. You can turn the engine by hand ....slowly just in case things are off and use a compression gauge in each cylinder to verify you are on the compression stroke. Once the cylinder is on a compression stroke, put in a reliable probe that you can measure the max height of the cylinder and follow the Firing order 1-4-3-6-2-5 for the 2.7t and 2.8. Just trying to think this thing out. I"m a chevy guy and the German stuff, particularity OHC cars are very new to me :(

As far as the 90/91/92 showing zero or +/- 1, Are you getting these codes from a ECU tuner/reader? I use torque pro. I know that if you do your timing belt, you must do two full revolutions of the crankshaft to pump up the chain tensioner. In the video below, at the 52 minute mark he references what I'm talking about. I only say or ask this because your comments about the timing tensioner chain possibly off a link. Good reminder to paint the sprocket and chain links ;) I'm a little concerned about my current engine removal while I"m reading your thread. I am in the process of removing my engine and rebuilding the engine because I will have to remove the heads, cam completely and start @ ground Zero. Not sure of this process as of yet.

LMK if I can help and if this helps...or not :) , it may help others in the future who use the search fcn, there seems to be few active members on the boards :(

https://www.youtube.com/watch?v=notzLin4dVI

[vtraudt]

Block 090-093 refers to measuring blocks in VCDS. VCDS is the software used to diagnose and service Audi and VW.
Timing on the V6 is done my popping the cam sprockets (on the exhaust cams) so they can spin freely, and locking the cam via cam lock bar (google) and locking the crank in TDC (via crank lock pin tool, google).
Evening out the tensions in the 3 timing belt sections, and applying proper tension on the belt (pull pin of belt tensioner, turn tensioner with allen key), you then lock the cam sprockets in position (tighten and torque the cam sprocket bolt).
Turning by hand a few times, then verify that cams and crank (TDC mark) are still right on .

After starting engine, verify with VCDS measuring blocks 090 to 093.

So far for the beginners basics.
All that has been done.

Question now is: what does 'cam phase' really mean?
How much would a cam chain link error (by 1 link) effect the data in block 090-093?
(I did NOT do a chain link count!)

[JTown77]

One Chain link off is huge! The valves are open/closed at inappropriate times. The system will try to adjust and will read the cams as out of phase. I have done this myself and the car ran, like shit albeit, but it ran. You'll need to pull the sprockets off and remove the cams.

The cam bolts are a one time use, I have reused them but torquing them a third or fourth time is going to produce bad results.

[Osmosis]

Thanks for the VCDS info. I use torque so I doubt I will see that info unless it is a CEL code.

The video vaguely refers to the tension and how to tension the timing belt once the proper torque is applied to the sprockets to the camshaft spindles. I also think that the video references the chain links need to be 16 on the camshaft chain tensioner area and 15 1/2 on the rear side. At this point, I think it would be worth the cost of valve cover gaskets to check. Imagine if you bent the valves and had to pull it all apart including pulling the heads due to bent valves because you were off a link.

I would also check for TDC through out the firing order. Simple procedure could also save you a lot of headache.

[LINDW4LL]

I doubt the chain is off if you didn't touch it. Sometimes I've found the lock bar is not perfectly precise. Mine is at -2 and + 2 even when using the lock bar and crank pin.

Block 093 should be within 6 degrees of zero for both banks, and also no more than 4 degrees in between banks as well.

So for example:
+4, -4 = not within spec
-4, +1 = not within spec
+3, -1 = within spec
0,0 = perfect

[Osmosis]

So, If I'm following this right, it is a necessity to have a vag-com to do the timing belt job? All I have is the torque Pro. I used to work for performance motor sport shop when I was in high-school and I built engines, mostly chevy, some Ford's. I understand engines well, but a bit distant from German stuff till now.

[86franklin]

So, If I'm following this right, it is a necessity to have a vag-com to do the timing belt job? All I have is the torque Pro. I used to work for performance motor sport shop when I was in high-school and I built engines, mostly chevy, some Ford's. I understand engines well, but a bit distant from German stuff till now.

Not a necessity for a TB job but you will have a bad time diagnosing some stuff if you can see what the sensors are seeing. And it will also show you codes the generic scanners won't. I personally use the xtool 401 vs vag com. No need to lug around a computer and it only costs ~$60. Just not as user friendly. But it operates in the same manner as vag com.

[vtraudt]

No need to lug around a computer and it only costs ~$60.

For basic needs: get $5 torque android app and $15 Bluetooth adapter.

[Osmosis]

I have torque pro and use it on my A6 and my F350...and my wife's Tahoe :) I purchased 3 blue tooth ALDL adapters, the best adapter I found was one that has a button on it to turn it off and on. Just seems to last with no problems. My other two have failed in 3 years, the button one I paid 20 bucks for has lasted 3 years running ;)

[86franklin]

For basic needs: get $5 torque android app and $15 Bluetooth adapter.

I fully agree. I have torque pro as well. And it's great for reading and clearing basic codes. But for any real meaningful information it isn't that great for Audi vehicles.