Administrative Account 7 Posted November 5, 2012 Share Posted November 5, 2012 I can't work this one out. It's an older model, 1999 to be precise, Volvo S40 2.0. The digital meter showing how many miles are left in the tank sometimes drops quite suddenly, one minute it says 120 miles left and then within another mile or two it's dropped all the way down to 25 miles left. If I stop for fuel at this point, upon removing the fuel filler cap a large amount of air gets sucked in, the meter will then go back to 120 miles left, likewise if I park it up and leave it for a couple of hours it reports the correct amount of fuel again. There is no difference in performance it's just a bit worrying about how much fuel is left in the tank. Any ideas? Cheers Link to comment Share on other sites More sharing options...
Administrative Account 7 Posted November 5, 2012 Author Share Posted November 5, 2012 Sounds like a blocked fuel tank breather pipe/tank cap which is causing a vacuum in the tank and causing the sender unit float to drop down and give incorrect reading. Link to comment Share on other sites More sharing options...
Scot 703 Posted November 5, 2012 Share Posted November 5, 2012 What he said. Link to comment Share on other sites More sharing options...
Administrative Account 7 Posted November 5, 2012 Author Share Posted November 5, 2012 I was suspecting something along those lines. Does anybody know how to fix it, if it can be fixed easily as a DIY job or do I have to take it to garage? Cheers again. Link to comment Share on other sites More sharing options...
Burnsy2023 2,895 Posted November 6, 2012 Share Posted November 6, 2012 Google for "volvo s40 fuel breather". Looks like it's a common issue. Link to comment Share on other sites More sharing options...
Recommended Posts