Porsche Cayenne Turbo S Crank no start - low compression

HI guys!

I have a 2006 Porsche Cayenne Turbo S (9PA) with about 200k miles here.
Symptom: Crank no start. it fires randomly while i'm trying to start, but it won't start at all.
There are only one DTC set in the engine Computer: P0480 -->Fan 1 control circuit

I checked the compression with a simple compression tester: All Cylinders have very low compression (5..7 bar) but all cylinders are full with unburned fuel! it really stinks from fuel! All ignition coils are firing well.
I've also checked the MAF-Value while the start process -->It jumps from 1000...5000 g/cm3 is that normal?

Are there any known Problems for the loss of compression? should the engine start with tha low compression? normal values are about 10..11 bar for this engine. The owner told me, the engine was burning a lot of oil before! I think this engine is dead, or did i forgot to check something? maybe a stuck Valve-Timing enhancer or something like that?

Thanks for any suggestions.

BR from switzerland
Matthias

Non-start and low compression could simply be due to bore washing with fuel. Jaguar AJ engines used to suffer non-starts once the bores got a bit worn due to bore washing causing major loss of compression if they got fuel flooded. What I used to do with those is disable the fuel pump or better the injectors the remove all the spark plugs and spin the engine over few times to clear the bore then put a few squirts of oil down the bore and spin the engine over two or three times. Replace the plugs and try to start it.

Thank you for this useful answer!

unfortunatly, the engine was running on it's own (very shaky) for few seconds after i wrote the first post. But it died as soon i pushed slightly on the gas pedal and didn't start again after!
Should the unburned fuel not be burned while the engine was running for this short period of time?
Maybe i should check the ignition Timing first, but i don't have a Amp-Clamp now because mine was broken few days ago