johns12

Looks like you are correct. Got the tensioner off and it looked in very good condition. Must have been changed at some point. The car has 120,000 miles. I replaced it with the new one since I had the old one out already. The drivers side cam cover has the original torx bolts.

turbo97se

Hello. I took a picture of the crank pulley. There appear to be two timing marks on it. There is no reference to them that I could find in Elsawin. Wondering which one should line up? I suppose I can try both and see which one it is... but waiting on tools and parts right now, I would like to turn it and see how far off things are on the cams

Thanks



Not sure if any one can tell if my cams are off from this picture just looking at the cam lobes. Can't see the holes at the front of the cam since they are at 90 degrees

turbo97se

I managed to turn the crankshaft and have the threaded cam holes pointing up .. they don't look as if they are out of time they point pretty much straight up .. any thoughts/advice?

FL C6.5 Avant

They would appear to be in time. did you get your took kit?
strongly suggest you pin the crank (see fastbird's thread).
but what I'm really dying to know is-- what is the history of your engine (miles, mx schedule, etc.?) Yours is by far the cleanest engine i've seen on the C6 boards.

turbo97se

Thank you for the reply, I do appreciate it. The car is 2008 bought new in 2009. There's only 55,000 miles on it. I thought it was rather dirty actually .. was a little embarrassed to post pictures since it is rather dirty.

Maintenance schedule is oil change every 5k miles, Mobil 1 0w40. Always change oil filter. Was in Colorado now in San Jose

The tiny crank notch pictured below does line up to 3 o'clock position. Thought I would put it in since no-one posted actual pictures of what that notch looks like.

I am waiting for the tools and tensioners to arrive but wanted to get familiar with the engine first so when the parts arrive, it would be faster to get everything in.

Wondering if it could be the exhaust valve timing solenoid at all or just cam position sensor? Thoughts anyone?

Picture of crank pulley notch:




Picture of where the crank pin will go. Torx T6 plug.

FL C6.5 Avant

Bravo. A man that takes mx seriously from the start.
I was referring to the internals. You have no sludge and almost zero varnish. yes, your vcg has been leaking at least on the pass side and you have dirt on the outside. no biggie.
looks like you already cracked loose the crank locking pin access port.

I don't wish to speculate on if your tensioners are bad or not. I will say that your engine is clean and certainly does not look like it has any blockage that would affect keeping the tensioner under pressure. You can see the hall effect probes in one of your earlier pictures. if you did not have any accompanying rattle, then you may try replacing the offending sensor, replacing vcg, and fire it back up. you could also remove the back upper cover (didn't see that you had done that yet) and see that the tensioner piston is still proud.
cnyman and fastbird may have some further suggestions since they have actually done the job, while i have not.

turbo97se

Thanks .. I will pop the upper back cover to check the piston is still proud .. this is the kind of info I was looking for. I tried swapping the sensor (intake swapped with exhaust) but it still has the same code. Checked power to the sensor harness is 5V from pin 1 to pin 3. It is the same on both intake and exhaust cam sensors. Hopefully, some of the other experts will chime in also. I think I will just switch out the tensioners regardless since everything is already on the way to me already.

cnyman

Since you switched the sensors and still have the issue, I would begin comparing the voltage from the other side sensors to see if you have a match in the voltage. Is the only symptom the CEL and the codes? No rattling at startup or during running? Your engine is pristine and I would find it really hard to accept that you have a mechanical failure. Also, check the connector very closely on the bad sensor bank as the pins can get misaligned and not make the proper connection. (Especially if someone does not know how unlatch the clip properly and forces it. Don't ask how I know). If someone replaced the valve cover and didn't handle the wiring properly, you could have a chafed wiring harness that might only malfunction randomly. Check or unwrap the harness where it hooks into the one going across the front of the motor and make sure it is whole and unmolested. I would even undo the protective covering to inspect the wires. Good luck. Wish I had read this post more regularly as I have all the tools. Will post them on the classified.

turbo97se

Long post .. but I have fixed the issue .. I checked some more stuff:

1. Exhaust Cam solenoid. I pulled it out and it looked fairly clean without any blockages.

2. The piston on the adjuster is very difficult to check since it is on the bottom part of the tensioner and space is fairly tight at the back of the engine. Everything seemed tight though.

I got the parts yesterday. I was under time constraint to get this diagnosed quickly .. so I went for worst case which was to order the tensioners. I switched out Bank 1 (US Passenger side). Didn't take very long to do it since I had it mostly apart anyway to check timing and stuff.

I followed instructions exactly and everything went smoothly .. but the check engine light was still there. Exhaust cam was off by anywhere between 6 degrees and 30 degrees according to VAG-COM. I tried to find a test mode to test the solenoid ... there appears to be one in the menu but could never get it to work.

Decided to look at the exhaust cam solenoid again .. still looked clean. Decided to swap test with bank 2 .. bingo! It was the exhaust cam control solenoid. Part number is 06E109257P. If I'd had had more time, I would have spent more time diagnosing this but the worry of the possibility of bending valves was driving me to get the tensioners done. At least I don't have to worry about the tensioners for a while.

Oh and I had 10mm bolts on the upper covers, no torx.I am sure they have not been replaced before.

Some tips for replacing the Cam adjuster tensioner:

1. Clean off the engine first especially around valve cover area, don't want gunk to fall into the engine. Plus it is nicer to work on a "cleaner" engine. I used some brakekleen to quickly do this but if I were to do it again, I would use pressure washer or hose.

2. There is pre-tension mentioned on the service manual. The original instructions did not mention pre-tension. Later posts mention it. Thought I would highlight it again. Thanks to the person that mentioned using light hand force.

3. When installing the crank locking pin, make sure to rock the crank back and forth when you are close to TDC. The pin doesn't go all the way in unless you rock it back and forth. I actually did not use the crank turning tool, I used the flywheel (flex plate) at the back of the engine to turn since I did not have 15/16" short socket to put on the tool to turn the Crankshaft.

4. The Cam adjusters have markings on the back of them "In" for Intake and "Ex" for exhaust. Check they have them and mark them if they do not have it cast in them.

5. The factory instructions were not clear on the tensioning. For the Bank 1, Right side (passengers side) you want to pre-tension the exhaust cam adjuster. On the Left side (driver's side) you want to pre-tension the Intake adjuster and tighten both bolts. You really need a long breaker bar to get these off and on again (90 degree turn was tough at the very end)

6. Lay some newspaper or plastic sheet under the car at the back of the engine. When pulling out the cam adjusters, there was quite a bit of oil that I was not prepared for. Either have rag handy or lay newspaper down. I hate oil on my garage floor.

For all the parts above, I used FCP Euro - highly recommend them. They price match and ship quickly. I did not realize that they had lifetime warranty on parts until another poster mentioned it. Thanks for that!

Tips/precautions on changing out the exhaust cam timing solenoids.

There is just one single torx (T-20) screw holding the solenoid in a recessed part of the valve cover towards the back of the valve cover pointing up like spark plug. Use some vice-grips (lightly clamp) to rock it and pull it out. After removing it, there is a LOT of gunk around the hole. I rolled up paper shop towel and stuffed it in the hole and then cleaned the gunk out. It is a horrible design. There is no way to clean it before you remove the solenoid that I can see. There's lot's of opportunity for the dirt to drop in there. The intake cam solenoids are not recessed (I did not need to change these) and are easier to clean. Lightly oil the o-ring on the new solenoid and put it in.

Here is a picture of the solenoid on the engine:



Now that one of these has failed, I see no reason that others will fail also but at least I know what to look for now. The cheapest I have seen for these are on Ebay for around $135. I was in a hurry and had to pay $178 at the dealer.

Hope this helps others.

FL C6.5 Avant

good news and thanks for sharing.