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Any idea where i can order to make a part?

Honestly it's exactly the same as the picture in the first post.

This was just to attach the hydraulic arm/strut to the trunk, that's why I needed it.

Unfortunately nothing is working so far.

I wired everything up, but nothing is working. I hear the pump vibrate, but it's not moving the trunk one bit. I suspect there might be a problem with the pump.

I'll double check the wiring to see if I made a mistake somewhere, but I doubt it.

This is how it's supposed to work once working properly.

If the wires to the pump are reversed the pump will run backwards and not pump fluid. I would check that first. To check you can take the hose off to the ram and run the pump to see if oil comes out, be ready for it and just bump the pump quickly. Also is there enough oil in the system?
edit: I am guessing this pump has 2 wires, if you reverse them the rotation direction reverses also.
There's two connectors, blue and white, going to the pump.

I dont know anything about these pumps.

I figure the blue connector is the power. When the blue connector is connected, and I press on the button, I hear whirring noise. Nothing changes when the white connector is unplugged. I wonder if the white connector is responsible for opening the path to the hoses?
On the other hand, I've put more than 500ml of fluid into the pump. I think the spec is about 300. The one quart bottle is about half empty.
At first, when running the pump, I had to add fluid for a few times, so I know the fluid has been taken up by the system.

Also, if I try to close the trunk by hand, I can feel resistance, so for sure I know the fluid is inside the line.
BTW I can post a picture of this bolt now that I'm next to the vehicle.

You can see how I had to relocate the attachment for the trunk hydraulic arm, because it's shorter than oem arm


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it looks like you have 2 wires coming out of that blue connector. Where do they go? Can you switch them where the connect to the car? Those should change the direction of the pump if you switch them.
I'm not sure if you can see this diagram. Those wires go to the module connector, Pin 1 and 2. I think they were in fact mixed up. When connecting the connector, white went to black, and black went to white.
I have no idea how thats possible, because the connector only goes in one way.
But I reversed the connections now.

I feel like the pump is working 20%.
if I press the button, it will start closing only if I pull the trunk a little bit.
And the if I push the button again, it will try lifting the trunk, but doesn't have enough force.
It can only lift the trunk of I raise it 80% of the way up. Then it will raise the rest of the way with great effort.

If the trunk is any lower that 80% of the way and I press the button, it will try to raise the trunk but I won't move up at all. It will provide enough power to prevent the trunk from dropping down, if I'm not holding it by hand, when I hear the motor working to bring the trunk up.

My friend is saying theres air in the system and after a couple of cycles, it should clear itself out.
However I tried about 30 times by now, and the pump won't close or open the trunk on its own.
Is it easy to check the fluid level? Or do just drain it and add the 300 ml? You dont want to much either. If it is made for 300 ml and you have 500 ml in it there may not be enough "room" for the fluid to move around.
The level should be good based on the mark on the pump. Maybe 300 ml is for the pump only. And the lined and strut took up the other 200ml.

I disconnected the 2 lines from the pump, and stuck them inside the hydraulic oil container, now just opening and closing the trunk non stop.
There's small air bubbles. But they seem to never end lol.
I wonder if it could be drawing air into the system somewhere else.
I'll pump the trunk another 50 times and try reconnecting to the pump


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No luck, unfortunately.
Not sure if the pump is too old/too weak? But it's just not enough power to do much, either to open or to even close the trunk.
Can you track down what the other wires do? Maybe they need to activate something to make the fluid flow better?
It is also possible that there are some parts stuck from sitting for a long time. That could be a relief valve or if it's a vane type pump they could be stuck. Let it sit for some time and try it every so often. Having new fluid in it may let it soak into small areas freeing up stuck parts, maybe.
There could also be a bit of something in there keeping something from working correctly... a blocked open relief valve or ??
Do you know if there is some sort of filter screen in it to keep chunks of stuff from going into the pump? That could be blocked with sludge or something keeping any oil from flowing....
Still quite a few possibilities to look at before buying another pump.
Honestly I don't know the composition of the pump, but I do have full diagrams, pinouts and a few tutorials of people who have retrofitted this system.
The pump has been laying around for a couple of weeks, it took me a while to wire up everything as per wiring diagrams.

I think the second connector on the pump is for the valve. Not sure if it doesn't open or what.
I purchased this set on ebay so I will probably replace the pump through ebay, before the return window closes.

I'm going to check over all the wires one more time, but I was super diligent the first time around.

I appreciate you trying to help
Yes I tried with and without the white plug, it seems to work exactly the same. If I help the trunk with my hands, to either open or close, I can tell the trunk is trying, but is very weak. So maybe something is not working, but I'm not sure how to test.

From the diagram it does seem there might be a valve. I'm not sure what the symbol represents, I circled it in red. 99% of people think I'm completely crazy trying to install this into my car, especially for the price :) So it's cool to meet the same type of person lol!
I will definitely let you know what was the issue, once I figure it out.

You see, this valve, or whatever it is, has 2 wires. One is ground, and the other one I'm not sure.
It's a yellow wire. I'm not sure if it's supposed to get voltage when I press on the open/close button or not.
I could try to supply voltage to that pin on the white connector, but since I don't understand how it operates, I don't want to risk burning anything.
I'm gonna have to ask my friend to measure voltage on the yellow wire, to see if he gets voltage on that wire.
If I should be getting voltage and I'm not, maybe the module is defective in not sending it out.


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I'm gonna study this diagram, someone created it for E38.
My vehicle is 39, but it must be pretty close

Do you have the tilt switch mentioned in the diagram? It looks like that tilt switch reports to a controller that shifts a valve to produce high or low pressure depending on the position of the trunk.
Yes i have the tilt switch. I had opened and examined it, it has a small metal tab inside that slides around, did not see any issues there.