Regular Member
391 posts
Posted 4 hours ago ·
I saw a mention on another web site about a guy finding lots of vacuum in the fuel tank when the fuel cap was removed. There is supposed to be a check valve in the fuel cap per the LS400 manual. OBD2 would not have that because of the self vacuum check the system does. So if the fuel tank is not letting air in that could be a problem for fuel delivery after a 15 minute or so run time. Just something to keep in mind.
How would i check this? I have noticed that when i remove the gas cap there is a lot and I mean a lot of air that comes out.