1998 Volvo V70 PO455- issues with gas fill

[ElGeorgito]

Hi everyone. My car has been slow to take fuel for a while. Usually I have to add fuel at the very slowest pump setting. Sometimes it can take 15-20 seconds to per l of fuel. Rarely it will take 25 l or so but then will fill the pipe and trigger the auto pump shutoff. It is also slow to take fuel from a jerrycan while idling. This car also has non functional fuel level sensor (at 400000k it will not be getting a new one). As a result I usually have no clue how much fuel is in the car. After running out of fuel a couple times I realize this problem needs fixing.

I have a 455 code showing. I think something has to be wrong with the EVAP system, but research reveals the EVAP system to be a horrifying tangle of hoses and valves. I read a post on MVS about the "EVAP theory of operation" that was very helpful. I suspect a bad Canister shut off valve. I am considering bridging the hoses that enter and exit the canister shut off valve in case the valve has switched to diagnostic mode (sealing the system for diagnostics is apparently its only function) and stayed that way. Purge valve and inside tank check valve are also suspect. Is there a way rig the system that will allow me to fuel this car? I don't care about any codes this may throw. Surely other people have run into this.

Please don't tell me to just hold the fuel pump nozzle halfway in or something. Thanks!!

[ElGeorgito]

Clogged charcoal filter to blame. Dont know how to get it out to change. It is located directly behind the fuel filter at rear of car. Awkward spot. Has anyone changed one of these charcoal canisters?

[volvooh]

So I have been getting the PO455 Code. I replaced the gas cap, but no changes. I was assuming it may be one of the hoses in the evap system, but it has been way cold and snowy here and have not been able to evaluate it.

Interesting twist though...when filling at the gas pump I have to do it very slowly, otherwise it starts to back-up and triggers the autostop on the gas nozzle, almost as if there is some sort of obstruction. Any thoughts? Looks like we will be getting into some warmer weather and I might be able to better address the issue.

[shegarty]

I am chasing the same codes on my 98 S70 and from what I have been able to find searching the forum the best place to start are the hoses around the purge canister (likely just behind the passenger side rear door right next to the fuel filter). After that there are a couple of valves but they are much more expensive so I am inclined to start with the cheaper stuff first. If your filling issues are just recent it might suggest that you have a backup of pressure in the tank that is causing the code - has this been happening just recently? I know mine is pretty finiky on the location of the nozzle and will trip the shutoff if it is placed too far into the tank.

[jblackburn]

Look for a clogged vent port @ the evap canister. Some 98s have the canister at the back; some have it tucked inside the front wheel well.

This will create a restriction in the EVAP system that does not allow pressure out as gas goes in, so the fuel backs up the pipe and shuts the pump off.

[bubbeck]

Howdy! Sorry to dig up an old thread, but I'm having the exact same problem, complete with P0455 codes and slow gas filling. Did you end up solving this? It just seems like too much of a coincidence that there are two separate symptoms involving the EVAP system that aren't caused by the same root problm..

[scot850]

To replace the carbon filter on a 99-00 AWD P80 Volvo requires the whole rear sub-frame to be dropped as Volvo thought it was a good idea to put the hold down bracket on the front of the filter making it in-accessible. On the 98, I think it is at the rear so is awkward but replaceable. I'm not 100% sure if the role over valve is positioned there as it is on the 99-00.

It is only a theory but I believe that folk that have this problem with their Volvos are the ones that have to try to get every last drop of fuel into the car, rather than stop when the cut out cuts the fuel filler pump off. Some cars are known to have this problem as it damages the carbon filters, and I am only speculating this is the case in cars where the fill issue happens as the carbon filter becomes blocked.

The 3 issues that can cause this are:

1) Blocked Carbon filter
2) Roll over valve partially or fully closed due to failure
3) Least likely but their is an air filter in some of the AWD filler pipes at the top that can get clogged with age which can prevent the tank expelling air as it fills.

Neil.

[abscate]

You have to be really careful which diagram you use from 1998 1999 2000 as they are all different and locations of components change.

[scot850]

OP lists his car as a 99 V70XC. The carbon canister should be at the rear above the rear axle by the fuel filter. The only difference in the AWD cars is 98 have a different mounting plate for the fuel filter/carbon canister to that of the 99-00. The earlier version has the fuel filter to the RH side of the carbon canister and the canister as stated before, I believe has the hold down bracket at the rear of the carbon canister. The 99-00 AWD have the fuel filter mounted behind the carbon canister, and the canister hold down bracket is at the front, needing the rear sub-frame to be dropped to remove it (thanks Volvo!).

If you want more pictures of the rear emissions system look at my rear sub-frame topic file:

https://www.matthewsvolvosite.com/forums ... =1&t=69887

There is a picture that shows the carbon can and the hold down bracket at the lower part of the picture. This is for 99-00 AWD.

Neil.