I've pulled the following two codes from my 98 S70 T5 and need help:

P0455 (Evaporative Control System - Large Leak detected) - I replaced the fuel cap about 5 weeks ago, but the code appeared again within a week. I'm told that it could be the Evap Cannister---how do I check? If not that, are there hoses or sensors that can be checked?

P0108 (MP0108 AP/BARO Circuit High Input) - This has appeared since the original diagnosis of the other code. Is there an obvious repair for this?

The evap canister doesnt go bad that often compared the the evap valve.The evap valve is located on the electric cooling fan on the battery side it has 2 hoses coming out of it.First check the hoses to make sure none are cut or broke.Some times people pull into parking spots and hit the parking stop and cut the plastic hose by where it meets the subframe.Check that first.As far as the other code there is a sensor mounted on the front of the subframe on the pass. side i think it refers to that sensor.The codes you gave are from an after marked scanner I know volvo codes not the after market codes.I think the baro sensor is also tied in with the a/c high pressure switch.Check those things and let me know.

Hey tech, do you have a picture of evap valve from a '98 V70? The trouble code P0455 started showing up on my car. I checked under the hood and did not find any loose or cut hoses. I checked the fuel cap and it looks good too.

No pics but it is located on the cooling fan like on the Battery side.