Hello,

 

I have engine 1.8tsi EA888 3rd gen 2015 CJSB and today when I started hear for 2seconds something like chain is about to tension and rattling.

 

Diagnostic is without problems, and values of phase between crankshaft and intake and exhaust camshafts are close to 0° (intake phase is right 0.0, exhaust -0.3° sometimes) - doesnt seem that chain is stretched.

 

VCDS:

 

camshaft adaptation intake bank 1 phase position is 0.0°

 

camshaft adaptation exhaust bank 1 phase position is 0.0°

 

Tensioner of chain is out of three threads from 7 allowed by VW.

 

video https://www.youtube.com/shorts/7O91BDjpFZc

 

Thank you

https://www.youtube.com/shorts/7O91BDjpFZc

It doesn't sound great that's for sure. Why are you so sure it's at position 3? Are you sure the tensioner is actually placing tension on the guide rail when engine is not running?

 

Related question. What is the wire around the tensioner ratchet teeth, that not the ratchet mechanism is it? 

you see on the photo that visible threads which are outside of mechanism are 3. VW service manual says that up to 7 it can be out of total 10threads. So according this it is ok.

When not running engine i wasn't able to press back with fingers via this hole.

Wire I think it it part of this part..here is some explanation

cant edit posts so today's cold start with better sound (open hood)

https://youtube.com/shorts/fwJkcLLEYkw?feature=share

Yeah ok, a sort of fail safe lock wire to stop the tensioner fully retracting in event of no hydraulic pressure.

 

Good photo of yours, never easy in there. 

 

If properly set up when new, according to those instructions, pull spring clip as far back as you can whilst applying pressure to both side rails to tension chain, i guess it shows your chain has stretched 2 tensioner clicks since installed.

 

Anyway, how many miles on your car?

Is itv original chain and tensioner?

 

The indicator as far as parameters is concerned is the phase adaption correction. I'd be most surprised if it was zero . I've never seen one at zero. Mine on a 70k mile gen 3 is at 2.2 to 2.4. It can vary slightly after fully warming up. 

 

Fyi. The intake and exhaust adaption values is to do with the variator for vvt. If you rev car, they should change. If it has vvt on both intake and exhaust. 

Edited 9 December, 20223 yr by TheClient
Typos

Coming from a mk6 Golf GTi as my previous car the gen1 EA888 suffered massively with tensioner issues. Although I think alot of it depends how often you drive it.

 

The issue with these tensioners, and Im pretty sure its the same with the older versions and this revision, is they work from oil pressure and I think keep a bit of pressure after turnoff. When the engine is off for a decent amount of time, the pressure drops and the tension on the chain drops so when car starts there is a few seconds of chain slap. This is how the chain skips timing, not often on driving but on startup. Im not sure if there is a mechanism to provide oil pressure

 

It doesnt sound great, I would advise getting someone else to have a look. Chain and tensioner replacement is a big job but luckily it seems to have given you the headsup with that noise on startup. As above, the values should be registering something.

Edited 9 December, 20223 yr by Dooge

Yes. Familiar with that. I had the old design in a gen 2 ea888 in a vrs mk2 facelift. Same engine as mk6 gti. 

 

Had the tensioner and chain updated yo revised spec. 

 

One of the biggest failures on the old design was the teeth of the ratchet retention failing. Or the band clip that held said teeth in. These locked the tensioner out when no oil pressure (I.e) engine off, to keep tension at startup. 

 

This is a gen 3 and the new design tensioner. It doesn't have the old rubbish design ratchet. These have limited problems reported but not out of the question to encounter some problem, especially beyond 100k miles or if timing chain stretch is an issue earlier. 

 

It would concern me that there is not enough tension being retained on the rail when engine is off. That's why the sound goes away as soon as hydraulic pressure builds. But if that is the case, and the noise is not something else, it leaves the engine at high risk of skipping chain teeth at startup.. that is how many, many gtis and vRSs died with the old tensioner.

 

Everything was fine until startup one day then -  she's dead.... 

i have 160k kilometers (100k miles), timing chain was probably not changed by previous owner.

yes I have new revised tensioner with threads, not old one with ratchet - teeth. But you mentioned wire on tensioner, maybe it should be as much as possible close to left side and then wire will not allow to retract tensioner back. I did photo after ride so it will be good to see from cold stard, if it is rewinded 2 threads... anyway technician says after seeing video that it is wrong tensioner (long life oil contribute to its failure)...

But I did cold start with VCDS, and phases were 0.0 degree also during this noise...

3 hours ago, mykro said:

i have 160k kilometers (100k miles), timing chain was probably not changed by previous owner.

yes I have new revised tensioner with threads, not old one with ratchet - teeth. But you mentioned wire on tensioner, maybe it should be as much as possible close to left side and then wire will not allow to retract tensioner back. I did photo after ride so it will be good to see from cold stard, if it is rewinded 2 threads... anyway technician says after seeing video that it is wrong tensioner (long life oil contribute to its failure)...

But I did cold start with VCDS, and phases were 0.0 degree also during this noise...

Ok. That is the sort of mileage you might expect to replace chain and tensioner - preventatively

 

Yes, that was my point re the wire clip ring. It looks like it should now be 2 rings closer to the left hand side - it does to me anyway, if it is doing what I think it is. Replacing the old style ratchet.... Or is there a ratchet mechanism still in there - I doubt it?

 

Technician says wrong tensioner? Why?

 

Yes, if your car has been on long life, it can contribute to chain wear / stretch and earlier failure.

 

On measuring the phase adjustment - the car will not provide a reading when first started, it has to idle down to normal 800rpm +-50 or there abouts.

 

On balance I would say based on what I hear and the mileage, that chain and tensioner need replacing.  You could take the top cover off. It is refittable. You can get a new seal but it should be ok. You could then try to lift the chain on the leading side of the sprocket but there is not a lot of room. You can also do the measurements between timing marks. Beyond that it is bottom cover off and a lot more work and bottom cover needs replacing and at that point you may as well replace the tensioner and chain at that point having got that far...

 

 

 

46 minutes ago, TheClient said:

Yes, that was my point re the wire clip ring. It looks like it should now be 2 rings closer to the left hand side - it does to me anyway, if it is doing what I think it is. Replacing the old style ratchet.... Or is there a ratchet mechanism still in there - I doubt it?

 

Technician says wrong tensioner? Why?

You see that I have newer one, 3rd gen has newer one with threads which are prone to rewind... there are no teeth which can be broken,

He says according sound, without doubts... dont know more.

 

 

46 minutes ago, TheClient said:

 

On measuring the phase adjustment - the car will not provide a reading when first started, it has to idle down to normal 800rpm +-50 or there abouts.

Ah ok  than I didnt see "tensioning process" when tensioner has no oil at start..... but technician says that I should start cold engine with diag... I did it but dont see any difference in measured values...

 

46 minutes ago, TheClient said:

On balance I would say based on what I hear and the mileage, that chain and tensioner need replacing.  You could take the top cover off. It is refittable. You can get a new seal but it should be ok. You could then try to lift the chain on the leading side of the sprocket but there is not a lot of room. You can also do the measurements between timing marks. Beyond that it is bottom cover off and a lot more work and bottom cover needs replacing and at that point you may as well replace the tensioner and chain at that point having got that far...

 

i will recommend to technician to replace the timing chain,... such a money but better as destroyed motor ... 

but still dont understand that diag is ok, tensioner is ok.... another opinion was that it is something with valves ...valve lifters or hydro tensioners (dont know proper term in eng. - part based on oil pressure which adjust valves)...

 

2 minutes ago, mykro said:

You see that I have newer one, 3rd gen has newer one with threads which are prone to rewind... there are no teeth which can be broken,

He says according sound, without doubts... dont know more.

 

 

Ah ok  than I didnt see "tensioning process" when tensioner has no oil at start..... but technician says that I should start cold engine with diag... I did it but dont see any difference in measured values...

 

i will recommend to technician to replace the timing chain,... such a money but better as destroyed motor ... 

but still dont understand that diag is ok, tensioner is ok.... another opinion was that it is something with valves ...valve lifters or hydro tensioners (dont know proper term in eng. - part based on oil pressure which adjust valves)...

 

Hydraulic Tappets was another thought I had but I've never heard then that bad.

 

The trouble with diag on chain tensioner most of it is non definitive.

 

The only two definitive tests are measure accross top timing marks for chain stretch. With bottom cover removed make sure chain is not slack!!! Everything else is only persuasive....