AWX is not starting - further troubleshooting steps?

Hello,

I'm having a problem with an AWX that won't start up after being shut down.

So far checked:

- Tax timings
- Fuel supply directly from containers
- Ventured under vacuum
- The PDE receives a control signal, which activates the magnetic valves.
- New submersible pump
- Initial dose of 50mg is displayed, as well as the duration of treatment.
- Angular offset KW/NW -1.6°
- Camshaft not misaligned with camshaft sprocket
- Starting RPM is okay, engine running with brake cleaner
- Compression OK
- PDE upgraded, seals replaced

and the car still doesn't start

Do you have any other ideas?

vwSchrauber wrote:

Do you have any other ideas?

Lid?

Have you ever measured the pressure in the tandem pump?

vwSchrauber wrote:

AWX doesn't turn on after being shut down.

How long does this "after shutdown" state last?

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Rear door?

open.

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Have you ever measured the pressure in the tandem pump?

Is neu, werd ich jetzt aber mal machen.....what is the target value for starting speed (approximately 270 1/min according to VCDS)?

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How long does this state "after turning it off" last?

Since last Friday

I have thoroughly bled the system again (creating a vacuum on the return line, starting), and I have used brake cleaner to assist, and it is now running

The likely cause is a combination of factors: the VFP (which I disassembled), and the compressed seals (between the inlet and return channels) on the PDE.

Congratulations!

vwSchrauber wrote:

I used brake cleaner to help, and it's running

Hopefully, the brake cleaner didn't cause any permanent damage... ?

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The likely cause is a combination of worn VFP (I disassembled it) and compressed seals (between the inlet and outlet channels) on the PDE.

You already replaced the PDE seals (-> first post)?

Was he then still dependent on the auxiliary pump of the fuel tank (VFP)?

How did you determine the shrinkage of the O-rings?
Is there a special explanation for this in this case, or can the fun bloom for every 1.9 PD driver sooner or later?

How old is the car? Distance covered?

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You already replaced the PDE seals (-> original post)?

Yes, but it only started after thorough depressurization and the use of brake cleaner.

I use brake cleaner instead of Startpilot because it burns much more gently, or rather, ignites later. Silicone spray also works, and you can even run the engine for a few seconds if you spray it while it's running, but I don't like the smell...

Now I also know why: the DiFi was at the top of the compression and was leaking, allowing air into the system when the engine was running.

In combination with worn VFP and shrunken seals, it simply wasn't enough to start the engine, or the battery was dead before the air was purged from the system.

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How did you determine the O-ring shrinkage? Is there a special explanation for this in this case, or can the fun bloom for every 1.9 PD driver sooner or later?

They were quite hard, and had hardly any overhang. The red (ancient) ones were still there. The upper seals towards the engine oil were still okay.

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How old is the car? Distance covered?

EZ 2001, approx. 190,000 km.

Thank you