While you have the system apart, replace all the existing rubber hose with new hose.

WRT to testing the sender, I just went through that with my jeep. I am aware of no test. But, as long as the sender arm has free movement, that is a good note. Not sure of the construct of your sender, but in general the arm does contact a circuit board which is the level indicator. I cleaned the contact points and made sure there was physical contact. When the tank was reinstalled, the level sensor does read more correct.

John Stewart
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