6R CBZB engine - vibration coming from engine at hot idle

[tromaras]

Hello I'm new to the forum, just bought the a Polo 6R 1.2 TSI 2010 with CBZB engine with 185000kms.|
First of all i did an preliminary service including:
1. Vag oil 502/505 5W-40 + Mahle oil filter with new sump plug and Liqui Moly ceratec
2. Mahle air filter
3. Man fuel filter (6 bar)
4. Mahle cabin filter
5. Bosch OE coil pack (new coil cables installed at 175k kms from previous owner)
6. New OEM PCV valve (and planning to install an oil catch can)

And planning to also service the:
1. transmission with Liqui Moly MTF 5300 70W-75W
2. coolant with Bilstein G12++
3. V-belt with Continental 6PK1693 ( water pump was replaced from previous owner at 120k kms, dont know the lifespan of those? any guess?)
4. replace spark plugs even though the have less than 15k kms, or at least check them for dirt/ carbon deposits and gap

TODO jobs
1. open the plastic timing cover and check the condition of the timing chain and which part (version) it is.

Now my problem is as follows:
<<(everything described above repeats every time i ride the car and i tries to describe the conditions as best as i can)>>

The car is in the garage for more than 3 days so its pretty damn cold.
Outside temperature is approx 15-20C.
I start the car and the idle goes above 1000rmp (approx 1100-1200rpm) for quick warm up and the tensioner ticks for less than 3secs then settles at low idle 650-700rpm steady.
I start my 15km ride urban and sub-urban so the car goes to operation temp.
After a while (7km) and when then car is pretty damn hot (at operating temp, no cooling fan on, no ac fan open, in neutral, clutch not pressed, when im stopped at traffic light) the idle is straight as an arrow, no ups and downs .. pretty stable --BUTT-- there is a vibration from the engine .. with steady rhythm ... That makes my furious!

Any guesses what it could be that and how can i solve it?

TIA and Nice to meet you!
*Pic for attention!

[wolfie]

Vibration or rattle? I found that mine had a rattle/rhythm. I chased it down to the fuel line that runs under and up through the chassis to emerge in the engine bay. Hold the pipe no rattle. Let go and rattle returns. I fixed mine by placing some stiff foam next to the pipe close to where it exits. (Mines a CBZB RHD)

Probably not that, but its worth checking as it is a zero cost fix so worth a look.

[tromaras]

Hello and thx for your reply, i certain that i feel vibrations because i can feel it at drivers position and the car shakes for a moment

[amer6R]

replace waterpump do it once do it right

[ciclo]

Everything you describe seems like normal conditions, except for that vibration. From the driver's seat, in my 6R TSI CBZC with 70K km I don't feel that vibration that you mention. I do not appreciate any type of vibration at idle, I did the service at 60K km.

There can be several reasons for this vibration, from a bad clutch or a worn engine mount, with 175k km it is correct to check the timing chain for elongation and its tensioners for wear.
The TSI CBZ is a widely known engine, maybe there is someone who will contribute more ideas.

A very interesting video, set the subtitles to your language in case you don't know Russian yet.
https://www.youtube.com/watch?v=LCPPYchl2sE

[amer6R]

Check crankshaft pulley?

[wolfie]

A very interesting video, set the subtitles to your language in case you don't know Russian yet.
https://www.youtube.com/watch?v=LCPPYchl2sE

Great little video that. I replaced the little breather valve on mine as it had broken exactly as shown there. I'm always hunting on "how to's" for the timing chain issues.

[ciclo]

Workshop Manual. 4-cylinder direct injection engine (1.2 l engine, 2V, EA111, turbocharger). PDF.
CBZB, CBZA, CBZC.

In case anyone needs to do any repairs:
https://drive.google.com/file/d/17fWB4F ... sp=sharing

[ciclo]

Check crankshaft pulley?

Hmm, I think it is more common on 3-cylinder engines, when the mechanic did not take into account the installation position of the crankshaft pulley to compensate for the vibrations of these engines.

[wolfie]

@ciclo
Cheers for the PDF link, very helpful as always

[tromaras]

Thanks everyone for contributing their ideas, im gonna give it a look on the weekend and ill report back. So far the list goes as follows:
1. replace spark plugs
2. check the hard line coming from the under the engine for wobbling
3. check the pulleys for loose bolts or alignment
4. finally go to dealer to check the engine mounts and the clutch!

Now I opened the service book again and found out that the clutch was changed at 120k kms .. maybe the mechanic who did that did now do a good job ?

Furthermore .. now when i drive more the car i noticed that on low rmp lets 1gear at 2k-2.2k rpm, when i change from 1st to second gear there is a "clank" noise ..
Im used to noiseless cars and i owned a Subaru impreza 2l turbo 1999 250ps ... so any noise i hear makes me angry

[amer6R]

Check crankshaft pulley?

Hmm, I think it is more common on 3-cylinder engines, when the mechanic did not take into account the installation position of the crankshaft pulley to compensate for the vibrations of these engines.

Shouldn't the pulley be keyed to indicate TDC position?
I know that these go bad on other cars like bmw, some people change them on 2.0 TDI.
Maybe he should give a look for wear, it wont cost him anything

[wolfie]

The 1.2Tsi doesn't have a harmonic damper built into the crank-pulley like many diesels and larger capacity engines, its basically just a plain pulley bolted to the end of the crank. It's only for air-con and water pump on the CBZB. All the timing is done via the crank and cam sprockets. Crank sprocket is interference fit, cam top sprocket is set when the chain is fitted. If the timing was out to any significant amount it would be showing DTC's. I think the ECU can measure the valve timing and anything more than 7.5 degs gets flagged as out of range. Plus the old school way would just car running sick.

[amer6R]

well the pulley isn't for sure.
Does this engine have some kind of EGR valve, if yes check that

[tromaras]

well the pulley isn't for sure.
Does this engine have some kind of EGR valve, if yes check that

No CBZB engines does not have EGR valves for sure ... i dont know what may causes the vibrations.
I didnt have enough spare time this weekend, but a gave the car quick inspection and i found the following:

1. first and foremost, i have the old cam chain with the silver cam chain tensioner probably revision 2
2. the fuel line coming from under the car through the engine bay is mounted to its bracket thus it makes no ticking noises
3. there is a squeaking sound coming from the v-belt section, visually checked and wiggled all the pulleys and none of them seems work (but thats with a question mark)

Questions: Any decent site or ebay seller in europe selling original oem part, im looking for the newer timing chain kit

TIA everybody