Don't you hate when something simple turns into a headache?
OK- background: had a few cracks in the flexible intake hose running from the air filter to the throttle body. Searched everywhere and had to order a $.50 piece of hose from the Volvo dealer for $43.00, which included a new plastic "elbow" that connects to the throttle body(I hope I'm calling everything by remotely the right name).
Take off old intake hose, disconnect hose and flame trap connector from elbow, figure I might as well replace it, too since I had to buy a new one. Put the new throttle body elbow on, and the receptacle on it that you insert and twist the flame trap into to connect it is melded so that the grooves are rotated too far so the flame trap connector won't stay in, and it's hell to even twist to get the little pegs to line up so it will even go in.

That's where the trouble began.
The flame trap connector has two hoses running from it. One is about 1/4" and just slides over a connector, alongside another much narrower tube, both of which are encased in an insulator and seem to disappear into the engine block.
While twisting and wrestling with it to try and get it to cooperate and go into the new receptacle, I sheared off the smaller tube about 2 ft. up into the insulating wrap, so that the whole thing came off. I just said screw it, cleaned and reinstalled the old elbow, with new intake hose. I slipped the larger tube back onto it's connector, but I can't even begin to fathom where the remainder of that smaller tube is or what it does.

Have I done something that needs immediate attention? What have I done?

I need to put a sign on the inside of my hood in large letters: If it ain't
broke, don't fix it.

Michael 1996 855 N/T 130k

The larger of the two flame trap hoses runs to a box on the engine block that traps oil vapor generated in the crankcase and routes it into the throttle body via the flame trap to be burned in the engine. The small FT hose is a vacuum line. From what you describe, I suspect you pulled the vacuum hose in two. This will create a small vacuum leak. Nothing urgent but it should be reconnected. Unfortunately, the other end is buried under the intake manifold. I'm not sure if the IM hass to be removed or not. There about has to be a way...

bl

I have a 96 850 N/A and I just replaced this two-hose combo as part of a complete PCV service (flame trap, oil hoses and vacuum hoses, clamps). The small vacuum tube that is broken here, I agree with the above poster that you broke it in half. On my car it runs under the intake manifold and connects to a metal nipple on the other side of the IM. The nipple is on the left side of the IM as you face it (passenger's side, very close to the thermostat housing). You can actually get to that without removing the IM. You could maybe replace the vacuum tube by installing a fresh tube that wraps around the front side, not sure if there is enough clearance to get it back in there to the flame trap.

But if you want to restore it to how it was, then get an updated hose combo that matches properly with your new plastic-elbow-to-the-throttle-body with the fused flame trap housing: go to www.fcpgroton.com and click to their PCV non-turbo link. The hose is about $45 but the really bad news is the only way to replace it is to remove the intake manifold. Get a Haynes manual for that and be patient, it isn't hard but takes a lot of time. Don't forget to buy a new IM gasket.

While you're in there you may want to just replace all of those PCV components, many people do it as preventative mainenance for protection from the dreaded rear main seal leak. If those lines were all clogged up with oil near the flame trap, and the plastic vacuum line was so brittle that it broke, you probably have oil crud in other PCV lines too.
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96 850 wagon

Is it possible he could just fish a new hose from the connection, through the mainfold, and back to the trap using a coat hanger and just abandon the old broken piece?

I suppose that's possible, but to the best of my recollection, that specific replacement hose is a real tight fit...a lot of stretching to get it to the end. Without the intake manifold off it would be a real chore. Personally, I would buy a piece of vacuum hose (dealer has it on a spool in the back) and just do it from the front.
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1998 S70 T5 Emarald Green Metallic, 2004 V70 2.5T Ruby Red, Previous Owner of Black '94 850 Turbo Wagon. My cars have been running so well lately they've got me worried.

Well, just an update...sure enough CE light came on, read codes and it's PO172(from memory)? Running rich. So at least the OBDII system's working. Now to decide if I want to tackle this repair myself and risk screwing something else up, or bite the expensive bullet and drop her off at the dealership.

Sounds logical. The vac leak is probably fooling the ECU into thinking the mix is too lean so it's enriching it to compensate. As Ev11 says, you can probably plug the leak at its source near the thermostat housing and "correct" the problem temporarly until you decide what to do. I was unaware where the flame trap vac hose originated. Think I'll look into his suggestion of running a new line around the IM instead of under it.