Rattle under valve cover (1.8T)

[eljay]

I decide to make a separate thread for this new issue I'm chasing.

Relevant car info:
2005 1.8TQ, GTRS, 034 Breather hose kit
175,000 miles

Engine-related maintenance in the last 3k:
- oil/filter change (Rotella T6 5w40 + Mann W940/25) with Seafoam treatment.
- air filter
- new coolant reservoir
- coolant flange and upper CTS replaced
- compression and leakdown tests (compression good, leakdown 2-3% on all cylinders)
- new spark plugs
- oil analysis by Blackstone Labs with everything in good spec except higher levels of silica due to poorly capped SAI tube port on the airbox (all fixed now)
- timing belt, tensioner, water pump, accessory belt
- valve cover and CCT gasket (there was leak around the moon seal)
- OEM 710P DV
- SAI blockoff plate (SAI removed by previous owner) and vacuum cap on N249 port.
- replaced vacuum hoses leading to the TIP/DV
- cleaned MAF

Items from TB down were just done.

Issue: there's a distinct rattle under the valve cover near the back of the engine by the CCT/CCA.
I think it was there in the past a bit, but I have just noticed it quite a bit after idling the engine when completing my TB service.

Here's a video. The vacuum cleaner like sound are the fans. This is from a cold start, so the idle settles a little and you can hear the rattling around 40 sec mark.

I am also getting a bit of a bounce in the throttle and boost gauge shows vacuum jumping slightly between -17-19 inHg. There's a Cyl 2 misfire code (P0302) as well. This idle bouncing has been happening for a while, but only recently have I been getting CEL for the misfire on Cyl 2 (plus the P0300 random code). I don't think that's related to the rattle, but I'm listing everything here.

As you can see in the video, I wanted to make sure it's not the new TB tensioner that's rattling/failing and it seems to be running smoothly. I did notice that when I just re-checked the tensioner to dampener gap, it's 6mm and when I set it, it was 8mm. I am still within 6-10mm range, so I hope that's good. The 6mm is there after 2 complete engine warmups.

So, I started to read on the rattle sound and found this great post by diagnosticator, which I think essentially says that the tensioner is rarely the issue, but the cam chain may get loose over time. Then I read some more and came across the oil pressure thread and I'm dreading what could be my next step.

I'm at 3k since the last oil change. Should I run another Seafoam flush and do an oil change and see if that improves the noise? Could it just be from some oil crud build-up inside? There was some dirt on the back of the valve cover, which I cleaned up and nothing seemed out of ordinary when I had the cover off.

Thank you!

[diagnosticator]

I recommend inspecting the timing adjuster guide shoes, at high mileage the shoes can come apart and fall of the adjuster. Also, the timing chain may be worn out. You should not be able to lift the chain away from the sprocket more than ~ 1/2 sprocket tooth depth away from the sprocket. If the chain can be lifted away from the sprocket 1/2 tooth depth or more the timing chain should be replaced.

[eljay]

I recommend inspecting the timing adjuster guide shoes, at high mileage the shoes can come apart and fall of the adjuster. Also, the timing chain may be worn out. You should not be able to lift the chain away from the sprocket more than ~ 1/2 sprocket tooth depth away from the sprocket. If the chain can be lifted away from the sprocket 1/2 tooth depth or more the timing chain should be replaced.

Thank you. Here's the only picture I took that shows the CCA area:


When I moved the CCA with compressed piston out of the way to install a new gasket, I could only move it a little bit on an angle. Not sure if that is an indication of the wear on the guides.
When I inspect the CCA again and remove the valve cover, do I have to replace the gaskets each time or am I OK to leave them as I just installed the fresh ones?

[diagnosticator]

The chain looks really loose in the pic. Notice how it droops between the adjuster shoe to the sprockets. The adjuster shoes wear from the chain sliding against the guide shoes, developing wear groves in the shoes. Replacement shoes with a new chain will remove the excess slack in the chain. You can reuse the cover gasket.

1.8Ts tend to sound somewhat busy in the cylinder head cover, but should not rattle.

[eljay]

Thanks. Can I assume that the adjuster is still working fine? I just don't want to be doing this twice.
I found this DIY. Wow, that looks like quite a job then.

Is it possible to replace the chain and the adjuster assembly without touching the front end and without removing the timing belt etc.? I.e. could I just move the intake cam as in the above DIY, remove the adjuster and have enough slack in the chain to take it off the exhaust camshaft sprocket?

Are these the pads I need? They don't seem to be available separately from Audi/VW, so I guess I'm looking for a good aftermarket version?

And a chain from Beck/Arnley or Iwis?

Can this loose chain also be the cause my misfires or is that a different unrelated issue?

[diagnosticator]

If there is clearance to remove the chain from the exhaust cam sprocket, then the timing belt does not need to be removed.

Yes, those are the pads needed.

I don't know about the Beck Arnley chain, Iwis is prefered.

The misfires are caused by something else.

[USAF Long]

My tensioner was shot and would rattle til the engine got warm. Every time I cold started my car it sounded like a rod knock or a clacking old diesel. I bought the one on ECS for $180 and it fixed the problem. The OEM one was like $800. F that.

[eljay]

If there is clearance to remove the chain from the exhaust cam sprocket, then the timing belt does not need to be removed.

Yes, those are the pads needed.

I don't know about the Beck Arnley chain, Iwis is prefered.

The misfires are caused by something else.

Thank you.

[eljay]

My tensioner was shot and would rattle til the engine got warm. Every time I cold started my car it sounded like a rod knock or a clacking old diesel. I bought the one on ECS for $180 and it fixed the problem. The OEM one was like $800. F that.

Was the actual tensioner gone and the piston not working or were just the pads on the tensioner gone?

I don't want to spend money needlessly, but don't want to do this twice with my high mileage tensioner.

Did you replace it yourself? Any pointers?

Thanks.

[gahigalaba]

i got the kit from Europa parts for the whole tensioner assembly and followed that same DIY. Was a lot easier than I expected. Biggest things to be sure of is counting links and torque specs. Be sure to get the tensioner tool and a new half moon and tensioner gasket. I put a little gasket sealant on them that I picked up from the dealer

[USAF Long]

You need a special tool I got it off Amazon. Mine wouldn't pressurize properly. Replaced it last fall, been silent since.

[eljay]

i got the kit from Europa parts for the whole tensioner assembly and followed that same DIY. Was a lot easier than I expected. Biggest things to be sure of is counting links and torque specs. Be sure to get the tensioner tool and a new half moon and tensioner gasket. I put a little gasket sealant on them that I picked up from the dealer

Thanks!

[eljay]

You need a special tool I got it off Amazon. Mine wouldn't pressurize properly. Replaced it last fall, been silent since.

Thank you. I already have the tool as I just replaced the gaskets. I guess I'll leave the new moon seal in there and replace the seal under the adjuster assembly as that appears to be a pressure seal, so I'm not sure that one can be reused. The seal is $5 in the US and $22 here in Canada. Lovely.

[Militant-Grunt]

My tensioner was shot and would rattle til the engine got warm. Every time I cold started my car it sounded like a rod knock or a clacking old diesel. I bought the one on ECS for $180 and it fixed the problem. The OEM one was like $800. F that.

The aftermarket ones fail prematurely. I would never recommend one to anyone, I know of at least a dozen people who went with the 'OEM' Brand, as well as the one ECS offers with poor long term results.

[old guy]

The aftermarket ones fail prematurely. I would never recommend one to anyone, I know of at least a dozen people who went with the 'OEM' Brand, as well as the one ECS offers with poor long term results.

Agree completely. Clicky click®

[CO AVANT]

I can confirm that. Just suck it up and buy the genuine OEM. I had a new one that was branded "OEM" and made by the same company that builds audi's tensioner. It's an HYT 088K. Has the audi rings on it and everything. Obviously not built to audi specs. Mine must have failed first 100 miles of my 2nd 2.0L rebuild. I had chased intake cam code over advanced faults for years never thinking it could be the tensioner after it had just been replaced. Started making good amount of noise recently so I replaced it with a true genuine oem. ECS actually sells a genuine oem audi tensioner and has a special on it right now for $704. My Intake Fault code gone finally. Can finally run with my CCT solenoid hooked up. For a long time I thought it was a tuning issue since everything else had been replaced.

[eljay]

With all the issues with non-OEM tensioners (even though this one on Europa Parts is claiming to be OEM - hm?), it sounds like diagnosticator's original advice is the best: just replace the shoes and chain and re-use the old adjuster despite the mileage.

I should also note that I don't have any CCA-related codes besides the misfire on #2 mentioned above that I need to chase down.

[old guy]

With all the issues with non-OEM tensioners (even though this one on Europa Parts is claiming to be OEM - hm?), it sounds like diagnosticator's original advice is the best: just replace the shoes and chain and re-use the old adjuster despite the mileage.

I should also note that I don't have any CCA-related codes besides the misfire on #2 mentioned above that I need to chase down.

If you read the post that I linked that was the CCA I had issues with. Twice.

[eljay]

If you read the post that I linked that was the CCA I had issues with. Twice.

Now that I've read through the whole thread (and your linked DIY!), it makes sense. I'll be ordering the pads and start there. Now that I know the cause etc., I should have found those threads, but I just didn't know what to look for.
It will be a while to get them, but I will post back once I replace them. Thank you!

[mosnet99]

OG for 2016 POTUS !!