Skoda Octavia 1.9 TDI PD ATD

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KarolMotronic
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Skoda Octavia 1.9 TDI PD ATD

Post by KarolMotronic »

Hello,

I have a problem with the signal from the crankshaft, the signal of the shaft for the last four
teeth before TDC is a bad signal.

On the new sensor happens to be the same, the teeth were checked by inspection camera did not show the broken tooth.

The car is a Skoda Octavia 1.9 TDI PD engine code ATD year 2002

Annex I add a chart with Pico

Thank you very much for all your suggestion on the topic :)

Regards Karol
Attachments
Skoda_20170223-0001.psdata
(8.67 MiB) Downloaded 524 times

dieseljohnny
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Re: Skoda Octavia 1.9 TDI PD ATD

Post by dieseljohnny »

Looks to me like you what your seeings is interference from the injector being activated?

Can you get a capture with more time on the screen and a current clamp on the common injector wire?
From memory a brown and yellow wire on the plug on side of head
Attachments
ATD octavia.png

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STC
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Re: Skoda Octavia 1.9 TDI PD ATD

Post by STC »

Hi Karol

I agree with Johnny, that is not a Crank Sensor or a "Broken Tooth" fault. And it is remarkably similar to a PD Injector Firing.
And a Classic Example of why an Inductive Sensor should not be measured AC Coupled, Note that it is pulled up by ~2500mV.

Your Pico Chart appears to be taken at Fast Idle - !800rpm. Is that correct ?
My thinking being that if that interference was real and reached the ECU Op Amp - that engine starting would be debateable ?

Please tell us what problems you have with the car ? Fault Codes ? ..... ..... .....

KarolMotronic
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Re: Skoda Octavia 1.9 TDI PD ATD

Post by KarolMotronic »

On a cold engine is generated fault code from the crankshaft signal G28 is incorrect. The car fires for the fourth time on a cold engine.
Several riots and the car behaves well.

KarolMotronic
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Re: Skoda Octavia 1.9 TDI PD ATD

Post by KarolMotronic »

I put signals

Channel A: The signal from the yellow-brown PD
Channel B: Signal crankshaft set AC

Thank you for your suggestions :)
Attachments
Skoda_Octavia_2002_20170227-0001.psdata
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dieseljohnny
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Re: Skoda Octavia 1.9 TDI PD ATD

Post by dieseljohnny »

If you could get DC signal from crankshaft that be great but you definitely have injector voltage on the crankshaft signal.

KarolMotronic
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Location: Poland

Re: Skoda Octavia 1.9 TDI PD ATD

Post by KarolMotronic »

I put signals

Channel B: The signal from the yellow-brown PD
Channel A: Signal crankshaft set DC
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20170227-0002.psdata
(6.31 MiB) Downloaded 450 times

dieseljohnny
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Re: Skoda Octavia 1.9 TDI PD ATD

Post by dieseljohnny »

Every time an injector is actuated your getting a reflection of it on the crankshaft signal.

You might have a bad control unit ,water ingress/corrosion in a connection etc...
Should check all powers and grounds for the control, loom for damage and connections for corrosion.
Attachments
ATD octavia 2.png

KarolMotronic
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Re: Skoda Octavia 1.9 TDI PD ATD

Post by KarolMotronic »

OK thank you very much for your response

I am a beginner in this topic, thank you again for your understanding :)


I will check everything again exactly the power, weight ,control etc ..

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STC
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Re: Skoda Octavia 1.9 TDI PD ATD

Post by STC »

On a cold engine is generated fault code from the crankshaft signal G28 is incorrect.
What is the Actual Fault Code ? P0335 / 336 ... ... ...
When does it set ? At cranking or once it has started ? (Cut the fuel supply to have it cranking but not starting)

I think for now you are on the wrong road blaming the noise - I may be wrong - we will see !

Could you post a Chart showing Crankshaft and Camshaft - both DC Coupled - with the time base set at 50 or 100mS/div. Cold engine, From Ignition on, Cranking, Idling then Fast Idle (2500rpm). Try to eliminate that "noise" by re routing the scope cables, keep the scope and laptop far away from the injectors.

Torsion Value in MVB's - Idling and fast Idle ???

I think I have an idea but would like to look at that information first.

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