[geronimomo]

Well, this past week I went to get my car inspected. It failed (as the title of this thread indicates).

My CEL came on last Sept. and I've cleared it a couple times. I cleared the CEL before I went for the car inspection and BAM. Failed even though no CEL. Drove it around for a few days and it's on again.

This is what I'm seeing:

And

I'm really hoping it's a simple fix as I hear the SAIP running at startup. Is there a DIY on how to check/replace the SAIP hoses?

 

[geronimomo]

Oh, the car is a 2005, V6, auto trans.

 

[Hirnbeiss]

Could be the pump, but check vacuum first. The thin plastic tubing going to the combi valves gets brittle with age, and is a cheap replacement.

 

[PZ]

You can run the SAIP with VCDS to see what sections of the system work. It will attempt to run the pump and open the solenoid. Narrow it down from there.

 

[Iowegian]

if the pump is running well it's probably either the piping from the pump to the combi valves, the combi valves or the vacuum that actuates the combi valves. Since you are getting faults on both sides I'd guess the combi valves are OK and either the plastic tubing from the pump is broken or you don't have enough vacuum to activate the combi valves.

You can check the combi valves with a vacuum pump or measure the vacuum with a gauge but the first thing to do is just physically check the condition of the plastic pipes from the pump and as mentioned above, the vacuum lines. Also check any relevant vacuum check valves that might be in that circuit too (if any, I don't have V6).

 

[geronimomo]

Yeah, I searched last night and saw a thread saying that

Could be the pump, but check vacuum first. The thin plastic tubing going to the combi valves gets brittle with age, and is a cheap replacement.

Yeah, found a couple threads saying the vacuum hose could be the culprit.. Found this thread but I'm not clear as the words are great but the pictures don't have any color coding.. Going to keep searching.

DIY: V6 Vacuum hose replacement

I just finished replacing my vacuum hoses this morning on my V6. It took a couple hours, but at least half of that time was cobbling together a solution for a mistake I made. I used the vacuum hose kit from ECStuning. It's currently on sale for $10. You'll need another 10 feet or so of 3.5...

www.passatworld.com

 

[geronimomo]

You can run the SAIP with VCDS to see what sections of the system work. It will attempt to run the pump and open the solenoid. Narrow it down from there.

Found this video from "The HumbleMechanic" about using the VCDS:

But I'm not see a selection to run the SAIP and test the system in the "Output Test". I'll have to look at the video again...

 

[geronimomo]

if the pump is running well it's probably either the piping from the pump to the combi valves, the combi valves or the vacuum that actuates the combi valves. Since you are getting faults on both sides I'd guess the combi valves are OK and either the plastic tubing from the pump is broken or you don't have enough vacuum to activate the combi valves.

You can check the combi valves with a vacuum pump or measure the vacuum with a gauge but the first thing to do is just physically check the condition of the plastic pipes from the pump and as mentioned above, the vacuum lines. Also check any relevant vacuum check valves that might be in that circuit too (if any, I don't have V6).

I'm going to have to sit down and research what you're suggesting..... Thanks!

 

[Hirnbeiss]

I'm going to have to sit down and research what you're suggesting..... Thanks!

He’s saying to get a flashlight and hunch over the back side of the engine. First look intently at all the vacuum hoses and lines to see if they’re intact. Personally I would just buy some vacuum hose and the thin hard tubing and replace it all while I’m there. If needed, you can use a Mityvac (handheld sucky thing with gage) to apply vacuum to see if it holds or you have a leak.

Also he is saying check the plastic discharge hose from the SAIP pump, which is nestled up front behind the bumper cover. That hose snakes its way up and back to the combi valves and also becomes brittle with age.

 

[geronimomo]

He’s saying to get a flashlight and hunch over the back side of the engine. First look intently at all the vacuum hoses and lines to see if they’re intact. Personally I would just buy some vacuum hose and the thin hard tubing and replace it all while I’m there. If needed, you can use a Mityvac (handheld sucky thing with gage) to apply vacuum to see if it holds or you have a leak.

Also he is saying check the plastic discharge hose from the SAIP pump, which is nestled up front behind the bumper cover. That hose snakes its way up and back to the combi valves and also becomes brittle with age.

I looked online and here to try and find a DIY video or something with pics specifically identifying the vacuum lines. Not too successful so far. What I've found so far is:

So far I think this is one of the pieces that should be replaced?

078129737A - Tpiece - Genuine Volkswagen Part

Genuine Volkswagen Part # 078129737A (078-129-737-A) - Tpiece

parts.vw.com

Also found this thread:

Vacuum line left out in every thread.

Hey guys, I was driving around today enjoying my exhaust drone and my thoughts began to ponder about my emissions when suddenly I realized that after like a year when I had changed my vacuum lines to silicone ones. I remembered that one line that runs behind the intake manifold which was torn...

www.passatworld.com

In reading the thread, I'll be needing a 6mm hose and a 3mm hose too?

I went to the EKTA section of this site and went through the engine, clutch pdf and can't seem to find the hoses and parts. I looked at 78 of 116 as it's for the V6 but I'm not seeing the T or the vacuum hoses. Perhaps I'm looking at the wrong pages?

 

[PZ]

Here is the solenoid and vacuum line for the Combi valves (far left), which connect to the SAIP.

This is the connection to the plastic tube that usually breaks:

This is where the hoses lead, the 2 large valves at the top side of the picture:

 

[Hirnbeiss]

In case you’re disoriented, start on the bottom picture. That is looking at the engine brom the back and below. The combi valves are those oil can looking things up on the backs of the cylinder head. When you hunch over from the top, you can follow the vacuum tubes that connect to them.

 

[geronimomo]

@PZ and @Hirnbeiss
Thanks for the pics and guidance.

I take it the lines I circled in red are the vacuum lines and the 2 devices I highlighted in green below are the solenoid valves? Is the blue item I circled the check valve?

The two items in the picture below circled in red are the combi valves?

 

[VAGguy]

Yes

 

[geronimomo]

Cool. It looks like the VW vacuum hose replacement kit is hard to get.

I'll have to buy the parts piece meal. How much of the vacuum hose do I need? In searching, the kit from ECS or FCP I think had a 1 meter long hose. Is that sufficient? I read that there is a hose that also goes to a "blue tank" on the driver's side that should be replaced? So that would easily be more than 1 meter in total. Perhaps 3 or 4?

I'll be taking a look at the car later on today.

 

[geronimomo]

Well, I looked and I broke something.... Dang it.

I was pulling on the hose circled in red to see where it ran down the front of the right cylinder back and the plastic hose broke and I heard a vacuum sound....

The line starts at the top, circled in red in the picture below:

In the picture below, top left you can barely see the blue of the connector to the right solenoid. The line is circled in red below. Bottom right of picture is where the line snakes down in front of the valve cover. The blue arrow is the direction I was pulling the line when it broke.

Below is another picture of the line in front of the right front valve cover. The left black part is the timing belt cover.

In the picture below, the line connected way back up to the solenoid is circled in red. The rest of the line, where the break occurred, is circled in blue.

When it snapped, I heard a hissing sound, I guess the vacuum being filled? I guess this is where the line may have been cracked causing my CEL??? I'm not sure where this connects to? I assume this is not part of the 3.5mm vacuum line?

I assume that it's still okay to drive?

Help please...

 

[geronimomo]

Doing research. I guess that's the line that goes to the vacuum reservoir. Now I need to figure out what size plastic line and silicone line I need to replace that. Also, guess I might to remove the left front fender to get to it? Wondering if that's the cause of my CEL...

 

[geronimomo]

Can anyone tell me if the vacuum line to the vacuum reservoir on the 2005 V6 can be replaced with the wheel well cover removed or do I have to remove the fender?

 

[Tortelious]

Can anyone tell me if the vacuum line to the vacuum reservoir on the 2005 V6 can be replaced with the wheel well cover removed or do I have to remove the fender?

You don't need to remove either.

DIY: Replacing all Vacuum Lines on 2003 B5.5 V6 (ATQ)

Below you’ll find my instructions for doing your vacuum lines. It’s a straight forward procedure and should only take a few hours. Thanks for all those at PW for their advice: ScottPassat2.8, keithermadness, JaytheSnork, PZ, ashman78, mrmom, and Steve in Chicago! You guys are a wealth of...

www.passatworld.com

 

[PZ]

I used about 10' of 3.5mm vacuum line to replace all of the plastic lines and vacuum lines on a V6. The vacuum line to the reservoir can be patched with a short section of vacuum line if need be. The hardest line is the one to the front of the variable intake actuator.