BMW N54 engine I need a good known Cam and Crank correlation

Maurice Business Development Manager Geebung, Australia Posted   Latest  
Question
Driveability
2007 BMW 335i 3.0L (N54B30A) 6-spd (A6HP19Z)

I am looking for a good known Cam and Crank Correlation capture for N54 3.0lt gasoline engine. I have attached 3 pico captures, one is from my suspect cam and crank, the other 2 are of my running compression test which I suspect is showing very high compression due the timing retarded.

Thank you

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Ray Diagnostician
North York, Ontario
Ray Default
   

What are the codes? I made GIFs from the 3 PSD files

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Joel Diagnostician
Soquel, California
Joel Default
 

I have a running compression wave form from an engine that was at 240 psi at idle very rough and the reason was low manifold vacuum due to vvt actuator getting stuck

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Maurice Business Development Manager
Geebung, Australia
Maurice Default
 

Thanks Joel I also was expecting maybe the same and wanted a good known Cam and Crank correlation pattern to go by. Strangely after disconnecting and re connecting the Cam solenoid my compression has returned to normal, so I do suspect you are right.

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Dmitriy Analyst
Toronto, Ontario
Dmitriy Default
 

Joel, indeed, with low intake manifold vacuum the compression peak will be higher, but N54 is just 10.2:1 compression ratio engine, so surprised to see that much higher. Which engine did you get 240 psi for?

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Joel Diagnostician
Soquel, California
Joel Default
 

Yes , 2006 jetta with 2.0 or 1.8 I do not remember , how ever I had 3 channel , incylinder , vacuum and spark when I catched you can see how the transition occurred in relation to each other

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Maurice Business Development Manager
Geebung, Australia
Maurice Default
 

Thank you Ray, I should have done this, I really appreciate your help. I will do a update to this case so everyone can see.

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Dmitriy Analyst
Toronto, Ontario
Dmitriy Default
 

These compression peak numbers are out of this world. Could you take a look how the combustion chambers look like with a borescope?

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Maurice Business Development Manager
Geebung, Australia
Maurice Default
 

Thanks Dmitriy, yes that is what I thought, after playing with the cam variable solenoid I actually got the compression pattern to look almost normal. So i feel there is a sticking cam variator. This car also has other problems which I will report on this case in a minute.

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Maurice Business Development Manager
Geebung, Australia
Maurice Resolution
   

The car came to me from another shop, it had an intermittent misfire which would come and go, the car would go into limp mode and we have fuel pressure fault codes, P294F High pressure fault, P29F3 Lower pressure sensor circuit fault, P29DC Cylinder Injector cut out. Replaced a faulty low pressure sensor and fixed P29F3, Diagnose Injector 1 and 6 was failing and I have recommended a new set to…

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