[Jerrycho]

Hello All,

If you have read my presentation, I'm french, so sorry for my poor english with mechanical terms.

Model:
PASSAT 3B5 - 2.3 VR5 Variant (Break Model) - 1999
F 3B-X-132 001>> * AGZ

I need your help. One of my vaccum line is not connected and i discover her during my cleaning.
On the technical manual, it should be plugged into the vacuum tank... but my vaccum tank est already connected with a line wich go in the car.

The vacuum tank for engine is the blue tank in the right of the engine ?

I drop 2 pics, I hope you can understand what i'm trying to say...
It's the line 44 / 45 / 46 on the diagram and I don't find the part 23 (bubble look ?), I have just the big blue tank.
Maybe if someone have pics for this lines ?



Lot of thanks for your help,
David

 

[PZ]

We did not get the VR5 engine in the US and the EU forums are fairly dead. I would trace the hose that is currently attached to the vacuum tank back and see where it connects. You don't need to use the exact same hoses to replace the damaged one you have. A parts store would have a good replacement, just measure how much you need.

 

[Jerrycho]

Hi PZ. Thanks for your help. I ll try to trace again the hose currently attached. I 've tried but the hose disappear under the driver side, under brake system I guess.
I read on other forums that vacuum system is connected to brake assist. It's true or vacuum tank is only for engine ? I saw no reference in repair diagrams.
But If this hose is disconnected, the vacuum system is not tight ? The brake assist should be disconnect to ?

I hope a european owner will se my bottle in the sea

 

[PZ]

The vacuum tank is used to activate the combi valve and the variable-length intake manifold during startup when engine vacuum is low. It should not affect the braking from what I have seen. For now, I would plug the hose at the open end until you can find a better solution.

You can try using a phone to take pics of where the other line leads to and maybe we can figure it out. There was also another Vr5 owner who posted a while back while rebuilding his engine and he may have pics. I off to bed now.

 

[Jerrycho]

I followed your idea.

I took pictures of this mysterious pipe



Pic 1, the pipe goes from the driver's side passing under the wheel axle and disappear.
Pic 2 : just to show you where I take pic (In the dark area under the coolant reservoir (which I moved here)

I did not find where it stood out.

The line is continuous from the tank until its disappearance.

Personally, I find it strange that my vacuum hose goes so far ...

I'm lost !
Do you have any ideas ?

 

[Jerrycho]

Hello everyone,

In my research, I found this image.
And I'm still lost with the mysterious hose ... I don't find this vacuum box on all others diagrams...It seems useless except for the engine
I wonder if I'm going to cut it to hook up my vacuum hose ...

Regarding the Solenoid Valve, do I have to be careful where I connect the hoses or not?

Thks a lot,

 

[PZ]

I followed your idea.

I took pictures of this mysterious pipe



Pic 1, the pipe goes from the driver's side passing under the wheel axle and disappear.
Pic 2 : just to show you where I take pic (In the dark area under the coolant reservoir (which I moved here)

I did not find where it stood out.

The line is continuous from the tank until its disappearance.

Personally, I find it strange that my vacuum hose goes so far ...

I'm lost !
Do you have any ideas ?

View attachment 102907 View attachment 102908

That is your power steering lines.

 

[PZ]

Hello everyone,

In my research, I found this image.
And I'm still lost with the mysterious hose ... I don't find this vacuum box on all others diagrams...It seems useless except for the engine
I wonder if I'm going to cut it to hook up my vacuum hose ...

Regarding the Solenoid Valve, do I have to be careful where I connect the hoses or not?

Thks a lot,
View attachment 102921

Honestly, I removed the vacuum reservoir from my car and plugged the lines. I saw no difference in how the engine worked and did not get any engine codes.

Not sure which solenoid you are talking about. Hook everything up like above, but with the hose for the vacuum tank plugged.

 

[Jerrycho]

That is your power steering lines.

Hi PZ,

Are you talking about the two big lines next to the mystery hose?
Can you tell me where they are coming from, to see if I can find the other end of my mystery hose?

 

[Jerrycho]

For you, if I "close" the line without connecting it to the vacuum tank, should that work?
I was talking about the solenoid above, but you answered my question, you have to connect them as indicated (logic in fact: D)

 

[PZ]

I could not see anything besides the p/s lines. I zoomed in and can see 3 lines under the p/s lines. I don't know what the hoses are as I have not seen them on a Passat before. I know there is usually a hose to the vacuum pump, but on the US Passats, it runs under the coolant tank to the fender, and down behind the fender liner. The fuel lines (pressure and return) run on the passenger side (in the US). If you have a vacuum pump, it's under the rear fender liner, and hooking it up to the vacuum tank might stop it from throwing a code if the gas tank is not sealing properly.

 

[Jerrycho]

Thanks PZ.

Today I will try to close the hose which is disconnected (normally connected to the vacuum tank).

I did not find a vacuum pump on the VR5 ... just the vacuum box (you can see it in the visual diagram)
I have a secondary air pump (with the **** EGR for pollution).

If the rain stops, I'll go for a test on roads.

 

[Jerrycho]

Result of today's test:

When cold (after 5mn warm-up time, and 10mn of "quiet" road) I managed to push the car on a straight line up to 4500 rpm, after this level, the car shakes and runs out of steam.
Then, when the car is hot, it started to block from 2800 rpm!

I unplugged the flowmeter, and the car didn't change its behavior ... So I don't think it came from him. I took it apart and it looks clean, but I'm still wary of electronics.

What's your opinion ?

 

[PZ]

I would always start with a compression test, but I don't think that's the issue as it gets worse when hot. I do suspect the catalytic converter, as they get worse when hot. Have you checked the output for the coolant temp sensor? Have you scanned the engine for any codes?

 

[Jerrycho]

Hello PZ.
How I can do a compression test ?
The catalyst is new (BM Catalyst). I haven't checked the coolant temp sensor, where is it? For the codes, I can not find any with my universal reader, but I think I would need a specialist. Do you have a model for me?

Again, thank you for helping me with my research.

 

[PZ]

I use VCDS, but you can get VCDS lite on a generic cable. I'm not sure how it is done, I know a lot less about software than about cars.
A compression test is done on a warm engine. with the spark plugs out, the fuel pump fuse pulled, the throttle body held open and a tool inserted into the spark plug opening. The engine is cranked several times and you mark down the numbers for each cylinder. Then post them here. Most auto parts stores in the US loan them out.
The coolant temp sensor can be read with VCDS lite. It may be faulty, leading to an overly rich condition, choking out the engine via overloading the catalyst.
Is the engine performing better than when you started working on it?

 

[Jerrycho]

Ok, I'll see to get VCDS.
I see ANCEL VD500, do you think it's good to read my car ?

Yes, when I started the repairs, the car was shaking as soon as I accelerated!
The problem came from the ignition, I replaced the coils and the spark plugs.
Now she has "only" this problem ...

I made these repairs:

• EGR cleaning
• new lambda
• New gasket covers cylinder head and throttle body
• new gasket for all intake system
• new catalyst
• The two solenoid valves (EGR and Vacuum)

I ll have a totally new car in few months

 

[PZ]

I would look for a generic cable like this, but do not run the software:

https://www.amazon.com/Aidixun-409-1-VAG-COM-Scanner-Suitable/dp/B08HCWKDFH/ref=sr_1_1?dchild=1&keywords=vcds+cable&qid=1618272185&sr=8-1

Then download VCDS Lite:

Ross-Tech: VCDS-Lite: Download

 

[Jerrycho]

Yeah ok.

I have a cable with an other software for my others cars.
I will try to connect with it and VCDS Lite, if it's not working, I will command a VAG spec

 

[Jerrycho]

PZ,

No success to connect VCDS with my cable.

BUT, I success to connect my other apps to my car :
I have these faults codes :

• 00543 - Engine Speed Sensor - RPM Upper Limit Exceeded
• 00553 - Mass Air Flow (MAF) - Sensor - G70
• 17924 - Intake Manifold Changeover Valve - Open Circuit -N156
• 01235 - Secondary AIr Injection Solenoid Valve -N112

I don't try a reset, I think the errors clear once they are fixed?

I think I can try to change :
First :

• Engine Speed Sensor
• MAF sensor (or all MAF ?)

Second
- My two solenoid, but there are new.