Opel Movano Fuel System Bleed: G9T Engine (2002)

Hello,
I'm having another Opel problem.
I replaced the timing belt. The engine started immediately and ran smoothly for a few minutes, but then it shut off on its own. Then it started again, but shut off again. After that, it wouldn't start at all, and eventually it started again, but only for a short time.
Okay, here's my current theory. The person who last drove the Movano likely drove it almost completely empty. Then, it was parked facing slightly uphill. The fuel gauge seems to be malfunctioning, and the low fuel warning light probably isn't working either. I tapped the fuel tank, and it felt empty. I added 10 liters of diesel and then "gurgled" it (presumably trying to prime the fuel system), which I probably shouldn't have done. I hope the high-pressure pump survived. If my theory is correct, and the problem is fuel starvation, then this might have caused issues.
There was an air bubble at the top of the supply line. When I open the drain screw at the bottom, nothing comes out. Instead, you can hear and feel air being sucked in.
Jetzt funktioniert der Anlasser auch nicht mehr. Kein klicken, klacken, nichts. Ich vermute fast eine Schutzfunktion. Could that be possible?
I've been searching online, but I haven't found anything definitive on how to properly bleed the fuel system. The engine is a common rail system from Renault.
Is it correct that you need to locate the diesel return line and draw diesel from there?
Does anyone know of a cheap system or a DIY solution for this? Can anyone recommend a cheap system for reading error codes? So far, I haven't even been able to find a diagnostic interface.

Thank you very much for your help.
Best regards,
Jörg

A pump ball is very suitable for bleeding air, and they also cost almost nothing.

Hello Jörg,

I think your Opel also has a pre-lift pump in the fuel tank, right?
If that's the case, it will activate with every ignition cycle. Therefore, you can also bleed your system by repeatedly turning the ignition on. Disconnect the fuel line to the high-pressure pump and wait until fuel starts to flow. Then, reconnect the line and turn the ignition on a few more times. The air should then be bled out.

Regards,
SK

Thanks to you all.
When I turn the ignition key, something makes a buzzing sound near the engine.
I did that repeatedly, but it didn't achieve anything.
If that's a pump, I'm not sure if it's self-priming.
I think I have to vacuum myself.
I found this graphic in the attachment. What, exactly, is a "pump sender"?

Okay, if I find or create something suitable for suction, I would first 1. completely saturate the filter, and then 2. continue working somewhere on the return line.

Then I also have the problem that the starter motor isn't making any sound.

Best regards,
Jörg

That buzzing sound is probably the pre-pump. It's self-priming!
Does fuel come out when you unscrew the fuel line leading to the high-pressure pump?

Regards,
SK

TDI-GTI-4-Motion wrote:

A pump ball is very suitable for bleeding air, and they also cost almost nothing.

bought

POR1 wrote:

That buzzing sound is probably the pre-pump. It's self-priming!!! Does fuel come out when you unscrew the fuel line leading to the high-pressure pump? Regards, SK

I haven't searched any further yet. I still had to install a new roof vent in the camper and warm up the motorcycle, and drain the oil.
I'm planning to continue tomorrow and will let you know.
Best regards,
Jörg

a pump is pumping.
A fuel sending unit sends the fuel level.

together a pump/sender!

Source: a time machine.
https://store.delorean.com/p-10569-fuel-pumpsender-module.aspx

Best regards,
gnash

gnasch wrote:

a pump pumps, A fuel sending unit sends the fuel level. together, a pump/sender! Source: a time machine. https://store.delorean.com/p-10569-fuel-pumpsender-module.aspx Best regards, gnasch

Then there should actually be diesel in the filter. I need to check again tomorrow.
Thank you!
Best regards,
Jörg

Hello Jörg,
The engine is made by Renault.
The rest of the car, but as far as I know, also .
That must be a Master, the one where they put the Opel lightning bolt logo on it...

You can find the diagnostic port (OBD2) behind the panel located below the steering wheel, near the headlight adjustment controls.
"Diagnosis can be performed using a Renault diagnostic tool, but it's neither cheap nor readily available. A universal tester, such as one from Gutmann, would work. Trying to diagnose via OBD2, for example, using VCDS, might be an option, but I don't think it will work."

Regarding the starter motor: The protective function is likely a large fuse, either at the positive terminal or hidden near the battery. This fuse is designed to fail shortly before the starter motor, and in some vehicles, the control voltage for terminal 50 (as VW would call it) is also connected to it.

And with the high-pressure pump, the first question is: what kind of pump is actually installed there?
Bosch CP1 or CP3. You should do a Google image search to see the difference, as the CP3 has a ribbed aluminum housing on the back, which makes it easy to distinguish visually.

The CP1 does not have its own booster pump; it is electric and is located either inside the tank (with a sensor) or somewhere in the line leading to the filter. The CP1 requires a minimum inlet pressure of 1.5 bar to operate; otherwise, it will not function. It does not need to be primed.

CP3 has its own gear pump for building up internal pressure before the high-pressure section.
In passenger cars, instead of a pre-installed electric pump, there's a hand pump located in the engine compartment for bleeding the brakes.
"In the case of tank trucks (where the suction height from the tank to the pump is significant), an auxiliary pump is usually installed. This pump is typically located either inside the tank or in the line leading to the filter. Normally, this auxiliary pump does not require separate priming. If there is no pre-feed pump, a priming ball must be present in the engine compartment."
The CP3 can run with a faulty pre-lift pump, but it won't be able to pump or bleed diesel very far, and it will usually have a lack of power because the damaged lift pump isn't supplying enough diesel.
So, if there's no pump ball there, then something is probably broken.
The noise is not coming from the electric pump, but from the motor.

Best regards, Christian.

Hi Christian,
Thank you for all the information. Today, I checked the fuel lines. There's a part in front of the engine that looks like a pump. At first, I wanted to take a closer look and remove the hose, but then I got worried about breaking something (so much is made of plastic these days).
Today, with two of us working, we were able to try more things – measuring, bridging connections, etc. We then approached the problem from a different angle, and that's when diesel started coming out of the filter when the ignition key activated the pump.
The starter motor also stopped working after a series of failed attempts to start the vehicle over the weekend. Multiple functional failures are often a consequence of mass production issues.
1. We were unable to measure any voltage at the starter motor.
2. Nor at the magnetic switch, depending on the position of the ignition key.
After a few attempts and some searching, we found a severely corroded main power cable. We created a temporary connection, and the starter motor started working again.
Tomorrow, I will create a new mass assignment and start from scratch again.
So far, I'm optimistic that we've found the bug.

I will report.

Thank you again to everyone who was concerned about me.

I might still need the information about bleeding the system while the fuel gauge is acting up...or maybe tomorrow, if I'm still going down the wrong path :-/.

Best regards,
Jörg

After swapping the main cable, the starter motor now turns again.
The engine started immediately, but then turned off after about 20 seconds.
We bled the diesel filter, repeatedly turned the ignition on and off, tried to start the engine, but it stalled again, and the whole process repeated a few more times.
It's running now.
I think the excitement is over now. I hope there aren't any other electrical gremlins hiding.
Now, there's another problem with the new power steering pump; the pulley isn't aligned. Hopefully, we'll be able to fix that too.

Best regards,
Jörg