Question regarding the VP44 and air in the intake

Good evening,

My V6 TDI BDG still experiences intermittent starting problems, even at temperatures above 15°C.
Occasionally, combined with the production of smoke for a few seconds.


The car is going to the Bosch service on Saturday, but I checked again today regarding air in the system.

The pump was newly installed a year ago.
The car had been standing for 2 days without being driven or started.

A friend got in and started the car, and I watched the approach line.

He finds an organ, approximately 4-5 seconds... nothing happened, nor did anything happen with the transparent supply tube.
Then it started up, and a larger air bubble in the hose diameter shot through the inlet.
Wouldn't they have already flown through the pipe during the organ playing?

Could this already be a reason for a failed start, or is it still nothing?

005,0,Initial Conditions:

Motor Speed G28: 812U/min

Injection rate: 33mg/hour

Injection start: 4.8° v, OT

Coolant
temperature (G62): 23.1°C


Would it perhaps be worthwhile to install another transparent hose in the return line?

Best regards, Steffen

A bubble won't mind at all.
The bladder is likely located at the top of the ESP and is pumped into the Difi after startup, and then returned from there back to the ESP.
The air problem becomes particularly problematic when many bubbles and foam run through the pipe.
Nevertheless, it never hurts to proactively replace the seal on the ESP.

Good evening,

The car is now at the Bosch service. They should check the pump.
If you're not going to fix it, I'm going to take a closer look at the intake. The escape routes, especially the air intake, are extremely clogged with oil.

I don't want to know how tight the intake channels in the head are.
I scraped out some {PAMPE} with a screwdriver from the {SAUGROHR} today and then reassembled it.

After the start, the engine really sputtered. Probably dragged some leftovers through...
Previously, the car was used as a driving school vehicle. Perhaps. Is he that way because of that?

How can I best verschandeln the suction channels to the valve without removing the head? Turn the engine until the valve is closed, then scrape it out with a spoon and then suck it out / blow it out?

Does anyone have a tip?

Have a nice Sunday

Steffen

The AGR (Air-Gas Ratio) leak is not the root cause! As long as the engine is running at its full power, it's okay. Some mm of mucus is normal.

Check the SPRAY START function in the default settings with a warm engine using VCDS!
As my doctor has already prescribed, some bubbles are normal after starting, but it should then be almost bubble-free after starting.

Since your engine is producing a lot of smoke after starting, it indicates a late fuel injection start.

Hello,

Starting smoothly in the default settings. It was also running quieter than usual there. The idle speed remains constant.

He was running at approximately 2n.OT...

When I only monitor the mwb 004 at warm engine temperatures, I observe jumps from approximately 2n.OT to 6.4 - 6.6n.OT, which occur sporadically. These jumps are also noticeable in the engine's running behavior.

I don't know where the jumps are coming from.
Funding should begin at 1 degree of OT, if I remember correctly.

Best regards, Steffen