VAG crank trigger wheel vs. CKP waveform

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tintoverano
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VAG crank trigger wheel vs. CKP waveform

Post by tintoverano »

hi,

the car in question is a 2015 Skoda Octavia with CKF engine

I did timing capture and got surprised by the CKP waveform

how can the trigger wheel (standard VAG group 60, 2 missing teeth) produce such a waveform?
cfk ckp.png

it looks like if there was a gap in the middle of the trigger wheel as well, which is odd looking at the trigger wheel in question (VAG 050105189B) - my first time with this engine

cfk crank trigger wheel.png

I found a timing capture at Rotkee and it is similar to the one I made

octavia ckf timing rotkee.png

what am I missing here?

thanks!

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Rfmotors1
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Re: VAG crank trigger wheel vs. CKP waveform

Post by Rfmotors1 »

Hi tintoverano,

It is very interesting post, assuming there are no DTC and no any problems but there are two missing teeth where should be not.

I believe that would be faulty trigger wheel, there is no need to have missing teeth in two positions in 4 cylinder engine.
To verify it, you would have to look on the same trigger wheel PN. physically to make sure, the picture from internet may not be reliable 100%.

So lets say the trigger wheel is bent and hall sensor fails to pick up two teeth which are accidentally on the opposite side 180 deg.
This can happen but if the engine runs normally, starts without long cranking and has not logged any DTC, then your case would be absolutelly fantastic for presentation, openning discussions and rising many questions.
Please upload the "xxxx.psdata" file if you can.
Looking forward for your updates.

Regards,
Roman

tintoverano
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Re: VAG crank trigger wheel vs. CKP waveform

Post by tintoverano »

hi Roman,

yep, no DTCs - just took the capture for looking at something else

I thought that there was a problem with the trigger wheel, but the known-good from Rotkee site shows the same CKP signal

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Rfmotors1
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Re: VAG crank trigger wheel vs. CKP waveform

Post by Rfmotors1 »

Hi and thank you for the update.

I understand some other good known waveform which someone else recorded has also two extra missing teeth.
However, if the trigger wheel does not have the extra miss, there is no possible a good sensor would miss it.
So I wonder, probably the same way as you do, what's is happening there?
The only valid evidence would be picture of the trigger wheel.
For now, it's cool mistery to me.

Please if anyone else has any comment to this topic, then post it here, I believe many forum users will be interesting to learn.

Regards,
Roman

liviu2004
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Re: VAG crank trigger wheel vs. CKP waveform

Post by liviu2004 »

2 teeths might not be iron (ferromagnetic) material.

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vasek
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Re: VAG crank trigger wheel vs. CKP waveform

Post by vasek »

Hi.
With the signal, everything is fine.
The rotor from which the signal of the crankshaft sensor is read has a different design,
and a different formula, which differs from the standard 60-2.
Attachments
CRANK SENSOR ROTOR+.PNG
CRANK SENSOR ROTOR.PNG

tintoverano
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Re: VAG crank trigger wheel vs. CKP waveform

Post by tintoverano »

Octavia 2015 CKF engine crankshaft

octavia 2015 ckf crankshaft.png

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vasek
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Re: VAG crank trigger wheel vs. CKP waveform

Post by vasek »

SKODA OCTAVIA 1.6 2.0 TDI CR ENGINES
https://mega.nz/file/81hiUIDZ#8a83NNONc ... -56bYHFhiQ

SSP316
https://mega.nz/file/ttxWTQJL#TCESULzpR ... -z1Gm-ITJk
.
Page 23 :
...The sender wheel consists of a steel ring, onto
which a rubber composite material is sprayed.
In this rubber composite material is a large
quantity of metal shavings, which are
magnetised alternately to north and south.
As a reference mark for the engine speed sender
there are two wider areas on the sender wheel
that are magnetised to north.
This results in a 60-2-2 sender wheel...

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Rfmotors1
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Re: VAG crank trigger wheel vs. CKP waveform

Post by Rfmotors1 »

Hi Vasek,

Thank you for the material you have posted. It's fantastic how this forum serves the purpose, it creates connection across the globe between people from various countries and different languages.

I will ask in my circles and if someone explains me the reason why VAG goes with two gaps, then I will post it here. Very interesting.

Regards,
Roman

tintoverano
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Re: VAG crank trigger wheel vs. CKP waveform

Post by tintoverano »

vasek wrote:
Wed Oct 04, 2023 1:26 pm
.
Page 23 :
...The sender wheel consists of a steel ring, onto
which a rubber composite material is sprayed.
In this rubber composite material is a large
quantity of metal shavings, which are
magnetised alternately to north and south.
As a reference mark for the engine speed sender
there are two wider areas on the sender wheel
that are magnetised to north.
This results in a 60-2-2 sender wheel...
great! thank you!

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