Hey everyone,

I just got I 1998 V70 GLT and I have a small problem. I got the dreaded check engine light, with code p0172, and I thought it was the 02 sensor. I was almost going to buy it, but then I went and checked the vacuum lines again, as someone recommended in this very same forum. I found that one of the hoses, underneath the thermostat and manifold, was broken. I really couldn't take a pic as it was pretty hard to access.
I then found this post, and that's exactly the same hose that broke in my car. The poster of that message fixed it by rerouting the line with some spare hose from AutoZone. What I can't exactly figure out is where the hose is coming from, so that I can do the same. If I am not mistaken, the end that's broken, is attached with a clamp underneath the manifold, but I don't know where the other end goes. Any help or input is greatly appreciated. Best regards.

Robert

 

Ok here is what you need to do. Remove that broken piece from the end of the intake and install a vacuum cap with a clamp.
Then look in the induction hose that goes from the Mass Flow to the turbo. Just before the turbo there is a Valve with a big hose and an electrical plug. It also has a small vacuum line going to the valve. About 2 to 3 inches back from the elbow that attaches to the valve cut the plastic line. Then run a rubber vacuum line from that plastic line and elbow up to an empty port on the vacuum tree under the throttle cover. Then you are done.
That is how it is done. You can route the new line through the metal brackets that hold the other lines that go from the front of the engine to the rear.

 

Tech,

First, I thank your for your response.
I know this might seem silly, but I'll ask anyway. I am not quite sure that I have found the hose that you are talking about, so I took some pics. First, there is a couple of pics from the broken hose:

Vac Hose 1

Vac Hose 2

As you can see, it's pretty tight in there. However, the main problem I have right now is that I am not sure where the hose connects to. To illustrate, and maybe so that it's easier for you guys to tell me how to do this, I took a pic of the other side of the engine, where I assume the hose goes:

MAF and vac hoses

Hose

In searching for the hose that Tech told me about, I found what looks like a hose fitting without a hose. Maybe it's nothing, but I thought I would ask. Here's a pic:

No hose?

So, to recap, could someone point to where the broken hose connects. I have looked and looked but I can't figure it out, and I don't want to screw up and cut the wrong hose [:-]. And the additional question would be, am I missing a hose, that goes to that empty hose connector?
Again, I thank all of you for your help, and particularly to Tech and Pak Chuck for their how-to instructions.







[IMG]local://upfiles/18398/C93B1E2587754848A617353C22C7A487.jpg[/IMG]

[IMG]local://upfiles/18398/BAC187FF4F064DD79482F4E47D9CFB75.jpg[/IMG]

 

Ok I made changes to your pic.

The red arrow is the other end of the broken hose thats the one you need to cut.
The Blue arrow is that conneected there?
Yes you are missing a hose.
I tried to figure out what hose goes there but cannot find it in Vadis.
Also my car doesn't have it I looked.

 

Tech,

You caught it, and I didn't, even though I was looking at it live! The hose with the blue arrow indeed goes to the empty nipple!

So, just to be on the safe side I'll recap:
1. I should cut the hose with the red arrow
2. I then connect a piece of generic vacuum hose to the now-cut hose (red arrow)(the guy at autozone gave me fuel line hose, but he said it was the same)
3. I should plug the hose that I just coupled with the red arrow one into one of the open vacuum nipples in the vacuum tree, underneath the throttle body.
4. And lastly, (or first) I put a vacuum cap onto the nipple where the broken hose originally connected, on the side of the manifold.

I have one more question. If I am able to fix this, then I still need to reset the check engine light, correct? I read in this post that you would have to, that the light won't go away on its own, even if you have fixed whatever the problem was. So, I guess my question would be if the scanners at AutoZone can reset the computer codes, or do they just erase them. I actually asked the guy at AutoZone, I told him that I knew what the problem was, and I asked whether he could clear it once I fixed it. He of course said no.

So, am I gonna have to shell out some cash to have my local dealer clear the code? Will they even do it? Thanks a million.

 

Yes you are correct.

They should be able to clear it no problem.

 

Hey everyone,

I have an update. I was able to remove the broken hose piece and clamp, and then I as actually able to connect the hose to the nipple, with a clamp and all.
However, I have not cut the hose at the other end, because it has some sort of cable or wire running inside of it. Is this normal, should I just cut the cable as well? Thanks.

Roberto

 

UPDATE

I just unhooked the original hose, and connected the new one. Thanks.

 

Ok, here are some pics of the "finished" job. I will reroute the hose, because it just started to rain here (any suggestions as to an alternate route?).

New hose at the PTC end:


Now at the intake manifold end:


And the routing of it:

 

Something happened to my pics. Here are the links.

New hose at the PTC end.

New hose at the intake manifold end.

New hose temporary routing.

I disconnected the battery and the check engine light went away, but I don't know whether this will do it, of if I do need to absolutely reset it with a scanner.
I know this might seem routine and/or small potatoes to most of you guys, but taking into account that I don't know the car, I don't know Volvos at all, and that I am not what you might call a brilliant mechanic, I am pretty satisfied (ask me about literature and then we are in business). I hope it works out in the long run. I will take it to emissions tomorrow or the day after, and see what happens. Any comments or suggestions are kindly appreciated.

 

You will need to clear the code with a scanner and maybe even complete a drive cycle before it will pass.
I will post later about routing.

 

I just came back from emissions testing: it passed!!!!!

The actual reading says that eh o2 sensor, cat, heater, and some other modules "are not ready", but this being Arizona... I don't know if the standards are pretty lax here, or the kid doing the test just passed it (unlikely, since the machine determines whether you pass or not), but all I care about is that I have my paper saying the car passed.

In any event, I am happy. Next I will do a coolant flush (drain and refill) and a transmission flush, just to be on the safe side. Thanks for all your help, and I look forward to your input about rerouting. Thanks a million.

 

Put the cap on like I originally said. Cut down the hose some and run it from the back of the motor to under the black throttle cover. There is a vacuum tree under there just attach it to any open port.

 

Will do. Thanks a lot.

 

No problem glad I could help.

 

Gentlemen, I too have an "EXTRA" vacuum hose on my 98 s70 t5. It comes out just below the vacuum tree and I cannot find the other end, or where to plug it into. I just did a PCV routine and I thought I had all the hoses labeled, but evidently not. If anyone has the answer I will be eternally grateful

 

Im new to this but did you find an answer?