Vacuum Elbow/Lines Question

[rmmagow]

98 V70 AWD LPT
Back where the turbo lurks there's a thing that looks like a small covered can (what's the name of this thing). There's a purple hard vacuum line connected to it with a rubber elbow. I think the elbow is starting to crumble on my car. A couple of questions:

1. Is this elbow in anyway related to boost control, P0243 CEL once in a while.

2. I would like to replace this elbow with a silicon replacement. At IPD I see elbow kits, blue silicone. Do any of those kits have what I need?

I would like to do a comprehensive vac line replacement using the brightly colored silicon lines as long as these perform better than the regular rubber ones. Are there kits available for doing essentially the whole engine compartment?

Being an AWD will I be able to find hoses/elbows in back, EVAP related lines?

Thanks Much

[jblackburn]

That's the air pump valve. Just get some vacuum hose (silicone or not, doesn't matter) and replace the whole length up to the radiator SAS valve.

Boost control, no. Not related to this, but may be related to the vacuum lines coming off the turbocharger.

I don't see any point in the silicone hose. The vacuum lines have lasted 13 years at this point; are you going to have that car in another 13 years? Just regular rubber hoses will do you fine, unless you really do just want the colored hoses.

[rmmagow]

Actually, I was thinking of colored simply so I know what I replaced. I anticipate a lot of rubber line related problems even though I can tell some are new. Hate to say it, if it keeps running, I'll still have it in 13 years. I have an old Mazda 929 that I've been driving for 20+, not to mention an old MB diesel at 26 years and another old MB at 55 yrs. Hell, the Volvo's the baby

[matthew1]

That Mazda 929 have the solar-powered ventilation system when the car's sitting? If so, does it still work?

Anyway, I've been getting tired of Volvo's dainty vac hoses and elbows. I've been replacing lines lately with heavy duty Gates vac line, about $1.40/foot if I recall. Re-routing if necessary to bypass the fragile OEM setup, like the one that goes from the PTC nipple to the Super Evil™ passenger side (North America) manifold nipple. The one that throws a P0172 if it's not on.

The factory routing is under the intake manifold. Pretty, but not functional. Mine's functional, but not pretty. See below.

No elbows needed so far, just nipple-hose-nipple, but I have a set of fresh replacement elbows I got from one of my sponsors just in case.

Function. Then form.

ptc-to-manifold-vac-reroute.jpg (189.05 KiB) Viewed 7077 times

Look Ma! No elbows!

ptc-to-manifold-vac-reroute2.jpg (267.13 KiB) Viewed 7077 times

[erikv11]

I like this fix. Nice one!

[matthew1]

Thanks. Fewer failure points = win.

[pkc303]

Good idea Matthew. I think I'll do the same when the time comes. Is the i.d. the same as the original hose, and just have a thicker outer layer, or is the hose actually larger?

[matthew1]

Inner is the same* -- 3/16ths inch I believe. And yes, outer is thicker than other vac hose I've seen. I'll see if I can dig up a closeup of the branding on the hose itself.

The PTC side I *think* needed expanding. I've done a few runs of this line from different vac tube A->B points over the months, and one of them needed some internal girth. I used a small knife to remove some hose material, plus I forced it over a gradual-larger diameter round chisel tool and let it sit for a few hours.


* same as the inner diameter of the elbows (not the thin factory tubes themselves)

[matthew1]

vacuum-line-replacement.jpg (70.73 KiB) Viewed 7006 times

[MoVolvos]

My PTC and SAS Valve have multiple rubber vacuum hose splices and the end to the SAS Valve is a long rubber hose making the 60+ degrees turn. Thanks for hose info matthew1 it looks very heavy duty.

Blessings,

BKM
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