Non-starting Cayenne

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victor2k
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Non-starting Cayenne

Post by victor2k »

Hello,
Today I made some captures on a a non-starting Porsche Cayenne /2004/3.2L.
The faults readed was P0335,P0344,P0369.
No support in Bosch ESItronic,so I can't be shure about the faulty singals from intake/exhaust camshaft vs crankshaft.
But I have the low compression on all cylinders(4,2 bar without any compensation/5 with compensation).Also the complete opening of the exhaust valve is retarded with 28*.
I can't find any reference in the Waveform Library,so I need info about some VW Touareg engine equivalence.
Thank you
Attachments
Porsche_Cayenne_2004_Petrol_20170901-0004.psdata
Intake valve open too early and bad adjustment of valve opening?
(2.82 MiB) Downloaded 525 times
170901_CompressionTest_001.pddata
(104.98 KiB) Downloaded 541 times
Porsche_Cayenne_2004_Petrol_20170901-0003.psdata
(5.22 MiB) Downloaded 602 times

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STC
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Re: Non-starting Cayenne

Post by STC »

Cannot help you with a known good cam/crank right now but what is the history to this vehicle?
With low compressions and late valve openings I'm thinking oil pressure, lazy hydraulic tappets ??? I'd be slightly intrigued.
In the light of Crank and Cam sensor faults then chain tension - also governed by oil pressure or not on this ???

Back to the fault codes. Just looked at the SSP for this, I'm sure you have too.

Couple of things, we don't often see faults for all 3 position sensors, newer cars will throw a correlation code. This should run without the CMP's connected. I would disconnect them both and Focus on the P0335 CKP code and make that go away. Then bring the other 2 back in one by one.

I'm guessing these errors have paralysed Spark and Injection ? Have they.
Do spark and injection come back with the 2 CMP's off ?

This could be an interesting one !

victor2k
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Re: Non-starting Cayenne

Post by victor2k »

STC wrote: Do spark and injection come back with the 2 CMP's off ?

This could be an interesting one !
No spark and injection on this engine and with both camshaft sensors disconnected the starter is engaged only for 1 second (maybe some protection disable the normal operation).
Best regards.

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STC
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Re: Non-starting Cayenne

Post by STC »

From SSP
The Camshaft Position Sensors (CMP) G40 and G163
Effects of a Signal Failure
In case of signal failure, the signal from the Engine
Speed (RPM) Sensor G28 is used instead. Because
the camshaft position and the cylinder position
cannot be recognized as quickly, it may take longer
to start the engine.
the starter is engaged only for 1 second
G28 Engine Speed Sensor
Effects of Signal Failure
In case of signal failure, the engine is switched off
and cannot be restarted.
Then it is possible you have a CKP issue and the ECU is allowing crank for a second, not liking and shutting it down,

I did wonder about CKP Amplitude and Magnitude - On the low side ?? Cranking Rpm's ???

Are you measuring CKP across the two pins coupled AC or Ground referenced, perhaps it needs to be floated above zero - have had that conundrum on a Vauxhall some time ago. Measure it To referenced to Battery Ground DC Coupled.

What if you power T50 at the relay and crank it for longer ?? Can you see ACCURATE RPM in actual values ???

Just some ideas.
Last edited by STC on Mon Sep 04, 2017 7:23 pm, edited 1 time in total.

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STC
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Re: Non-starting Cayenne

Post by STC »

You ignored my Oil Pressure Theory - Why ???

victor2k
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Re: Non-starting Cayenne

Post by victor2k »

STC wrote:You ignored my Oil Pressure Theory - Why ???
Hello,
Until now I don't have any measurement what confirm/deny your theory...
Regards

landroverman1958
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Re: Non-starting Cayenne

Post by landroverman1958 »

Hiya,as stc has mentioned,there is a sensor in the sump area which will stop the engine starting if there is an oil pressure problem,which also will disable the fuel pumps, i found this out on a cayenne turbo setember 2004 model,ther is information available on identifix in usa, :wink: i hope this is of some help,regards,

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STC
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Re: Non-starting Cayenne

Post by STC »

Oil pressure Light or Gauge on the cluster. How long for it to go out, and how fast it comes back ????

Live data if available ?

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Re: Non-starting Cayenne

Post by STC »

I digress off topic for a moment.

Hi Landroverman.
there is a sensor in the sump area which will stop the engine starting if there is an oil pressure problem,which also will disable the fuel pumps,
Recently I saw a Ford Transit with a failed Temperature Sensor that paralysed start, thinking it had overheated / is too hot.

May help someone one day.

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STC
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Re: Non-starting Cayenne

Post by STC »

Hello Again Victor
with both camshaft sensors disconnected the starter is engaged only for 1 second (maybe some protection disable the normal operation).
Maybe consider this:
http://www.scantool-direct.co.uk/automo ... 327-p.html

Use it to confirm deny the theories. I have one and never leave home without it.

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