98 V70 NA evap system leaks question

[98v70dad]

I don't think I have the SAS system since I don't see it on the vacuum tube routing diagram on my hood. I haven't spent the time with a flashlight looking for the air pump but I didn't see it on my quick look yesterday. The Volvo thumbed its nose at me recently by throwing code p0455 about 10 minutes into my daily drive to work at a stop light. It always happens at a stop light, usually in the morning when its close to 30 degrees. The hose routing diagram part number on my hood is 9454020. The one on my hood is in an awkward spot and is really tough to read but my memory is that I've already replaced everything on the tube routing diagram except the seal between the vacuum tree and what it attaches to. The charcoal canister wasn't replaced but it passed my very close visual inspection about a year ago. No cracks and no areas that looked distressed. All new parts are volvo and the rubber hoses are either volvo for the molded ones or gates for the vacuum hoses.

1) I wouldn't be surprised if the o-ring at the flame trap connection leaks (even though I've replaced the o-ring) because it doesn't fit tight and the hose connection there puts a torque on it which pulls the connection open. I've noticed in pictures on this website that people have slathered that connection in RTV silcone, probably to get it to seal. I've resisted doing that because it makes future maintenance difficult but wonder if there are any other common solutions people have tried for this spot?

2) I did not replace ANYTHING in the fuel tank area except the gas cap. I bought a short(4" +/-) tapered hose that goes under an access panel (don't remember from where to where) and set it aside "for another time" when I realized how much work it would be since what I did up front a year ago corrected the codes. I've been emissions code free since unti lrecently. I remember that the access panel and what I was trying to gain access to were not aligned, so when I cleared the codes by the other fixes I declared victory and stopped. I am ignorant of what other things may need attention in the fuel tank area regarding evap leaks and would appreciate any good suggestions. I know the seals to the gas tank, the sending unit and fuel pump sometimes go bad. I don't smell any fumes and had planned to leave those for last. What else commonly goes bad?

3) I also did nothing with the tube that goes from the gas tank to the charcoal canister. Is this a rubber line or one of those hard plastic lines with rubber fittings on each end? How do people fix this line or is it not typically a problem?

4) this one is more out of curiosity than anything else. The hose that goes into the intake manifold on the passenger side is very difficult to put on. Is there something special about that vacumm there as compared to the vacuum available at the vacuum tree? When looking for my hose routing diagram (never found) I noticed that some versions of the car take that hose to vacuum tree instead of the intake manifold. It would be easy to do this and then you could just cap the nipplet on the passenger end of the manifold. Any thoughts on this?

[erikv11]

Here is a start:

For the air pump, it is also very informative to just look at the air box. From IPD's web site:
And it is really obvious to just check whether or not there is a tube from the fitting to the air pump, can't miss it:


(1) I've got nothing beyond the RTV solution, I have tried that one. It's a bit messy but it does work. Oh you can replace all of those parts, hose and flame trap housing, that might do it.

(2) I can't answer this one very well without searching, maybe others can.

(3) Don't know, have never messed with that one.

(4) I would not be afraid to try what you suggest. I have seen people connect the IM nipple to the tree, but not the flame trap nipple to the tree. But given the variety of diagrams out there your idea sounds reasonable. No harm in trying it seems? Maybe hook up the new route then do a glove test, monitor mpg.

[98v70dad]

For item 1) I've been considering getting a junkyard intake tube (the big plastic one) and cutting off the plastic port or nipple that attaches to the flame trap end of the the big pcv mod heater hose. In its place would go a brass plumbing fitting of some sort that would replicate the orifice size in the original part (they must have dropped the diameter dramatically for a reason. This would be easy to attach to with a screw clamp and easy to seal with a couple of neoprene washers. The plastic part that holds the flame trap would be discarded.

Thanks for the easy ID on the SAS system. My car doesn't have it which is nice! Still looking for comments from anyone who might have some knowledge regarding these questions.

[98v70dad]

So, I stopped by the used part store on Friday evening and picked up a newer elbow and an brand new fitting. When I started "going in" to replace them I noticed that vacuum line from the intake manifold had fallen off (zip tie didn't do it). The new parts fit tight and seemed to seal up good. The old parts were loose and probably leaked like a sieve. Everything got a stainless screw clamp this time. We'll see how it goes.