98 V70 gas tank - possible vapor build up issues

[erikv11]

You may have checked already, I didn't review the tread, but since you said p0172: is the elbow and line good on the passenger side of the intake manifold?

[98v70dad]

You may have checked already, I didn't review the tread, but since you said p0172: is the elbow and line good on the passenger side of the intake manifold?

Yes, I think so. I inspected it and amazingly it looked nearly new so I didn't replace it. I bought a new one and have it standing by if I need it. When I did the PCV system upgrade I got rid of the plastic tube that ran under the manifold and replaced it with a piece of brake line with a 90 degree bend on the passenger side. The line runs on top of the manifold along the front of the fuel rail. The brake line fits snugly in the 90 rubber elbow but I cinched it on tight with a screw clamp. The rubber 90 elbow is just pushed onto the manifold with no clamp.

So, my brake line idea has me out there on my own a bit, but I really think its much better than the original design. The brake line was pretty cheap also.

[erikv11]

Yeah, that sounds like a pretty good fix. I figured you were aware of that one but wanted to ask.

[98v70dad]

So I replaced the purge valve with a volvo part and the filter next to it this weekend and so far no codes. The old filter was absolutely filthy. I dont know if it was plugged. I didnt think about checking it until it was buried under two days of garbage. I'm not going to dig it out.

Also, I filled the gas tank this evening and buried the gas pump nozzle into the filler neck. The pump didn't shut off or skip a beat. I put in 12 gallons at max velocity and the pump didn't shut off. I dont know if this was a coincidence or just good luck, but this hasnt happened for at least 2 years.

[erikv11]

This is interesting. Which filter are you talking about, is it something on the filler neck like Neil posted about?

[98v70dad]

This is interesting. Which filter are you talking about, is it something on the filler neck like Neil posted about?

There is a little filter between the purge valve and the charcoal canister. It looks like a lawn mower fuel line filter and is located about 4 inches away from the purge valve in the engine area just aft of the radiator on the drivers side. I've read that most people remove them because they "only cause problems". For whatever reason I left mine installed. It cost 6 bucks and since I already shelled out 102 for he purge valve, I splurged. I'm just wondering if the purging wasn't happening because the line was plugged. Working now, at least for 100 miles ...we'll see.

[98v70dad]

So its been a few fill ups and many days since I replaced the purge valve and the filter. No codes since, no shut off of the gas pump during fill-ups since, no swoosh of vapors when removing the gas cap since. Apparently either the purge valve or filter or combination of both wasn't allowing the system to purge.

[jreed]

Sorry for the delayed reply to your question a week ago. Yes, there are two electrically actuated valves in the system, a purge valve and a vent valve. The purge valve is mounted near the radiator in the engine compartment. The vent valve location depends on model year. On the '97 it is behind the front wheel on the driver's side. On the '98 I think it is located near the gas tank.

[98v70dad]

Sorry for the delayed reply to your question a week ago. Yes, there are two electrically actuated valves in the system, a purge valve and a vent valve. The purge valve is mounted near the radiator in the engine compartment. The vent valve location depends on model year. On the '97 it is behind the front wheel on the driver's side. On the '98 I think it is located near the gas tank.

On my car, a 98, there is an electronically actuated valve on the aft side of the drivers side wheel wheel. I know its there because I've replaced it and it was a royal pain to do. Most people refer to it as the rollover valve. I have nothing electrically actuated in the rear near the gas tank that I am aware of.

[erikv11]

Rollover valve is a strictly mechanical thing, turn it over and it closes, no electronics (that would defeat the whole purpose). Pretty sure they are only back near (just aft of) the fuel filter.

There is a tangle of stuff on top of the gas tank, maybe that is the location jreed is referring to? You would never see it unless you dropped the tank, or did some serious poking around with the fuel pump hatch up.