Blinking MIL on....running rough.....where to start with repair?

[lswing]

For my benefit, lack of knowledge, that is a split down the middle (busted) "cam chain tensioner gasket"?

Cam tensioner pad...$30 as opposed to $800 for complete unit.

[Aronis]

I see all the comments and I agree.

I did not have a record of that part on my parts list in 2012. He is convinced they were new.

I had the car in for replacement of the oil pain seal (liquid seal not a gasket, who knew) and at that time we both were present when he took the oil pan off. There were pieces of plastic in the pan.


He told me that the next day he inspected the CCT and said they looked new. I did not at that time quite understand what it took to actually inspect these things.

So now he said he looked at them again during my engine pull and they were new.

This is what I think really happened.

They WERE NOT REPLACED in 2012, thus not on the part list D'ooh. The parts in the pan were SOME PARTS of it, but the device had not failed yet. When he inspected them, he did not pull the valve cover on the passenger side since that required the engine to be dropped a bit and I know he did not do that back in 2012 (otherwise I would have had to get an alignment.) He may have peaked at the DRIVERS side CCT and made the conclusion that it was ok, and it may have been ok. I think a chunk broke off in such a way that a "eyeball" look at it could have missed the chunk missing if it was a clean brake from an end or something.

Now the parts have failed and that is why the passenger side is -12 on the phase and the drivers side is +7 on the phase because I suspect mechanically they are mirror imaged and the phase shift would be opposite?

So big shit I guess, I just was going to have him replace the CCT at the time of the pull but they are $700 each, and for that service it would have been about 12% more total. D'ooh.

The questions is:



VS:



Who has use the non brand name part???

Or should I just replace the guides (apparently this can be done? Part numbers)

Mike

[P1054]

As I recall, each bank of cams has one tensioner with two pads per tensioner (one on top and one on bottom). You can't see the bottom pad on EITHER side with just a quick glance, they're pretty well tucked in there. I believe both the top and bottom pads are the same. I had one of my upper pads fail and my car immediately sounded like an old diesel tractor (the steel chain was riding on the steel tensioner piston instead of the pad, which was in pieces in the low spot below the tensioner). When I pulled the valve cover off, it was VERY obvious the pad failed. BUT, had it been the lower pad instead of the upper pad that failed, it would have taken a close inspection to see it.

As for fixing your situation Mike, my suggestion would be replacing all four pads and leaving the tensioner assemblies. Obviously you'll want to inspect them for any damage caused by the pad falling apart (grooves worn by the chain, over-extended pistons, clogged inlet filters, etc), but in my case the tensioner assembly was still perfectly fine and worked great after I replaced the pads. (Pads = guides = the little plastic pieces that the chain actually contacts, and that seem to have a tendency toward falling apart)

Also, make sure the mechanic checks around under the valve cover and gets rid of any residual pieces of plastic. They probably wouldn't cause any major issues, but it's easy to do and keeps them out of anywhere they shouldn't be.

[P1054]

For anyone who hasn't seen them before, this is what new pads/shoes look like. (Note there are four, one top and one bottom on each bank).

[P1054]

And for further reference, here is a complete tensioner showing both pads (this image is of a 1.8T tensioner, but the 4.2TT ones look nearly identical). The lower shoe in the photo is the one that is quite difficult to see when it's installed.

[P1054]

One more thing I'll throw out there, just found this article: http://forums.quattroworld.com/a8/msgs/65935.phtml

It seems that the broken pad COULD be caused by a failing tensioner (lock pins sticking)? Article is about the D2 S8 engine, but I'm assuming they use the same tensioners.. Can anyone with ETKA confirm?

[DHall1]

I get it but really still this is BS

The engine was out and all this stuff was apart. No way these pads were inspected! Both valve covers should have come off to inspect esp the pass side!

So here we are. Doc Peiserg's car had engine out service last year at 125k and both pad sets were replaced and its been perfect to 150. The engine is perfect and sounds tight.

I would put pads on and let them eat labor.

I see all the comments and I agree.

I did not have a record of that part on my parts list in 2012. He is convinced they were new.

I had the car in for replacement of the oil pain seal (liquid seal not a gasket, who knew) and at that time we both were present when he took the oil pan off. There were pieces of plastic in the pan.


He told me that the next day he inspected the CCT and said they looked new. I did not at that time quite understand what it took to actually inspect these things.

So now he said he looked at them again during my engine pull and they were new.

This is what I think really happened.

They WERE NOT REPLACED in 2012, thus not on the part list D'ooh. The parts in the pan were SOME PARTS of it, but the device had not failed yet. When he inspected them, he did not pull the valve cover on the passenger side since that required the engine to be dropped a bit and I know he did not do that back in 2012 (otherwise I would have had to get an alignment.) He may have peaked at the DRIVERS side CCT and made the conclusion that it was ok, and it may have been ok. I think a chunk broke off in such a way that a "eyeball" look at it could have missed the chunk missing if it was a clean brake from an end or something.

Now the parts have failed and that is why the passenger side is -12 on the phase and the drivers side is +7 on the phase because I suspect mechanically they are mirror imaged and the phase shift would be opposite?

So big shit I guess, I just was going to have him replace the CCT at the time of the pull but they are $700 each, and for that service it would have been about 12% more total. D'ooh.

The questions is:



VS:



Who has use the non brand name part???

Or should I just replace the guides (apparently this can be done? Part numbers)

Mike

[Aronis]

I greatly appreciate all the input.

What about the lesser expensive brand of CCT setup. I am concerned about the possibility that the tensioners themselves may be near failing and at this kind of milage and at the cost I think I should replace at least the Passenger Side one. I guess I can go with the Audi branded one for 700 but the other one is only 200 bucks. My understanding is that the same actual manufacturer makes both the branded one and the generic one.

Who would use OEM vs aftermarket (apparently made by the same company?)?

The drivers side can be replaced without too much trouble but he wants to replace the TIMING CHAINS on both sides. I don't quite understand that. How would one assess the Chains? They are $140 or so so not too expensive.

I am looking at :Valve Cover gasket set (third set in the past 4 years), new seals for the CCT, new chains, the guides or entire CCT assemblies.

The labor unknown, $100,000 or so I am sure.

Mike

(should have dumbed the car when it started leaking oil)

[P1054]

The chains ride on the tensioners. If you have a tensioner out, you'll have the chain out too. If the chain has been riding on metal for a while, I suppose it could be a good idea to replace them.

[DHall1]

Check genuine for a price on the pass side tensioner if you feel like changing that side.

I keep a 50k mile oem sitting on the shelf for a rainy day.

[Bigglezworth]

220K vs new....

[DHall1]

Yep

this should have been a must do at your mileage.

Its more important than the bufkin pipe really.

[lswing]

I have my fully functioning 98k adjusters with new pads if needed. Although at 98k, I'd be tempted just to put in 0k ones. I searched for months for the closest to OEM pad, looking at mold marks and detail stamps that matched up. Will dig up link...

[AndyRS6]

Everything you need in this set http://www.blauparts.com/proddetail.asp?prod=GF21011-1G
Me personally, I would change just pads (already in set).
To change chain both cams need to be removed.

Your quote : Next step, back to service position, and drop engine a few inches to allow access to that F-ing coolant pipe to allow cam the be services on passenger side
Just curious why engine drop few inches? I did few times with out doing so.


Andriy

[Aronis]

Thanks,

P1054, thanks that makes sense

DHALL so that's a no go on the brand X (Bapmic)

Biggles: Great Photo! Picture worth a thousand words.

Iswing: If I swap the unit it will be with a new one

Andy: Your photo is very tiny LOL, How did you do it? Loosen the mounts to the coolant pipe ,or "Flex it?"

Mike

(pissed off.......should have known better and swapped both when the thing was out of the car)

[SteveKen]

You dodged a bullet there. My tensioner guide on my D2 S8 failed which broke the chain which broke the timing belt which bent a couple of valves (strangely) on only the opposite bank.

The only way you can inspect the underside guide is to remove the tensioner, and you can't remove the tensioner without removing the cams. It's a big job just to inspect them, so I'd consider the biting of the bullet and resign to have the guides replaced rather than just pay the labor to have them inspected since it's all apart and exposed.

With the cams out, the head needs to be cleaned of all the leftover bits of guide and you will need to pass a rod through the oil return holes in the head to be sure that no bits are stuck in these holes. Then, for peace of mind, you need to drop the oil pan again and get rid of anything that my have fallen in there.

Also, it's effortless to get leakdown numbers when the cams are removed and all the valves are closed, too.

[Aronis]

He confirmed the stamped part number on the CCT and the number is the newer number and not the original part. So I guess the mechanical/electric part of the CCT are ok to keep and just replace the guides and the chain....

Mike

[SteveKen]

The CCT's do go bad over time and are unable to maintain pressure when the oil pump is not running.

It can sound really bad when the car is first started until the oil pressure builds back up inside the unit.

If you search the quattroworld D2 forum, a guy cut one open.

I replaced the check valves under the valley pan in my block and replaced one of my tensioners with a lower priced one and my timing is now perfect.

However, I started it up last night after sitting for about a week and things sounded poopy for a second or two. Might be the entire enginre in general or from the tensioner that I did not replace.

I do suspect that this dieseling at startup can make the guides wear faster, though.

I'll be sure to run it every coupe of days instead of waiting a week from now on.

I guess what I'm getting at is that you should consider replacing the tensioners as well.