My answer to the original question would be that it can't hurt, but the problem you are experiencing could simply be diagnosed to such a problem by watching fuel pressure during the event.

As to the mess from the other tank, it must of been a diesel. KE cars really don't take well to contamination. On many models we will pull the tank sensor and look in the tank with a light.

BTW, if you find it rusting, get a new tank.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician