Is this a potential vacuum leak source?

[yojaywuzup]

Hello All,

I looked at my gas tank inlet connection today looking to see if that might be the source of my evap leak callout and I found a couple things that didn't make sense to me and was hoping to get some feedback from the forum. I have included pics as well to help.

the white piece in blue circle is what puzzles me.

the white piece in blue circle is what puzzles me.

What is this white piece for and is it supposed to have a hole in it. I do not believe so and am hoping it isn't a relief of some sort, but any help would be great here.

Secondly, I have read that if you smell gas when you take the cover off, that means you have a leak there, but I didn't really see any obvious leaking at that cover. Here is a pic of what might be some residue, but I don't know if it is significant.

the white piece in blue circle is what puzzles me.

If this ends up being my problem, is this an easy fix or will it be a brutal process?

Thanks,

Jay 97 850 N/A

[jblackburn]

That piece is supposed to be there. I'm not sure what it's for; my guess is that the same housing can be used for another car in the lineup. Can you smell fuel vapors through the little dent that appears to be there?

Usually EVAP leaks can be traced back to either a bad gas cap, or the lines coming out of the tank itself under the car up to the EVAP canister, wherever it's located on your car.

[17yearsofboost]

exactly- 1 housing multiple applications. unused in your case.
I doubt your EVAP leak is traced back to right here,
But a strong smell of gas here with the tank sealed is probably reason for some further investigating

[yojaywuzup]

Good to know it is not supposed to have anything plugged into it. In the last picture the inside of that unused connection has a hole in it like something punched through it. Is this normal then?

To address the fuel smell, i didn't smell a strong fuel smell, but you can smell fuel and I was curious as to what signs I should be looking for if it were leaking there.

Thanks Again

[Red-Arrow]

Guys what is the test procedure for the Evaporation canister?

[jblackburn]

It looks like that piece just has a plug on the inside to keep it from venting or anything.



I would start your search elsewhere, unless you do smell fuel vapors from inside the trunk.

[PerthX]

Ok my '95 850T gave me a check engine light and the following A2 code 315 which say "EVAP System" and an A2 code 435 "Catalytic Converter Efficiency Low" ... and also a code 435 "Slow Front O2 Sensor"

Is this EVAP the same thing pictured above and is this a major issue? I assume the codes go together. First time I ever had these codes before and I just cleared them awaiting to see if them come back.

However, if I fill the gas tank I usually smell gas until it is down to 14-15 gallons so I usually don't fill past there. Replaced the fuel filter last Summer and it didn't help the smell when full.

Also, could this be a part of why I get only 22 mpg (did a full tune up last Summer and no change to mpg.) Where and what is an O2 sensor?

Anything you all can guide me with would be appreciated.

[Klausc]

Good to know it is not supposed to have anything plugged into it. In the last picture the inside of that unused connection has a hole in it like something punched through it. Is this normal then?

To address the fuel smell, i didn't smell a strong fuel smell, but you can smell fuel and I was curious as to what signs I should be looking for if it were leaking there.

Thanks Again

Check with your local dealer about 850 fuel tank repair recall. For an Evap leak, it is best to check the ends of the line from the tank and the charcoal cannister (behind the front left bumper area). Just look for cracks.

[SkyVolvo]

PerthX-
Based on my own experience, the o2 and cat. codes both come from a dying o2 sensor. The vehicle has two oxygen sensors that screw directly into the exhaust stream; their job is to measure how efficiently your engine is burning its fuel (if there is too much oxygen passing through, it's not running at peak efficiency). If the sensor itself no longer measures accurately, it gives bad info to your car's computer, which then adjusts its air/fuel ratio incorrectly, causing it to run rich.

Your front o2 sensor, located between the engine and the cat. converter, is probably dying its slow death, just like mine did. They last for a very long time, but eventually need to be replaced. You will almost certainly see a jump in MPG - mine went up 2-4 mpg after I had it replaced.

The o2 sensor is a pricey little piece, with direct fit replacements clocking in around $100-$140 if I recall correctly, but should certainly be replaced for your fuel economy and the health of your catalytic converter, among other things. From what I've read, direct fit original manufacturer parts are the way to go in this case, as others have had problems with aftermarket universal sensors (though some people claim they work just fine).

As for the evap code, try screwing in your gas cap a little tighter, and if that doesn't work, try replacing it (these are the simplest, cheapest, and most common fixes). My car sets this code if the cap isn't tight enough.

About the o2 sensor: there are plenty of tutorials on replacing it yourself, but you'd probably be better off finding the best deal you can on one, and paying someone else to put it in. Despite my strongest efforts and healthy dousing of PB Blaster, I only succeeded in rounding mine off (despite using an o2 sensor socket...). Then I crushed the thing completely when I tried a new approach. Then I took it to my Volvo guy, who got it off and replaced it without any issues and at a very reasonable price.

Also, when my car was adjusting for the bad o2 sensor, I lost a significant amount of turbo boost, which returned after it was replaced and the codes were reset.