Charcoal in fuel filter?

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Sep 14, 2012
SW Washington
Car = 2003 Pontiac Grand Am 4cyl Ecotec. Fuel pump went kablooey and while changing it I also changed the fuel filter. On a lark I cut open the old fuel filter (OE ~ 90,000 miles) and it was black with what looks like carbon/charcoal. Could charcoal from the EVAP canister be finding it's way into the gas tank? Is this at all normal?

GM says there is no maintenance interval for the fuel filter, replace as needed(!!). I have decided a 50,000 mile fuel filter change is maximum but if there is charcoal from the canister getting into the fuel tank maybe there is more maintenance I should do?
Depending on the can location i suppose it could get saturated with fuel if you top off the tank and find its way into the tank. I don't know, i never gave it much thought.
I would guess its more likely decaying rubber scum of the inside of the hose that connects the filler pipe to the tank.
Decaying rubber scum. Sounds like a punk rock band.

The fine screen filter on the fuel pump was quite clean so the black particles either went through the fine screen or came after that. I suspect that they were small enough to pass through the fine screen but not the filter.

So it is unlikely that the charcoal from the EVAP canister can get into the fuel tank? Good.
Originally Posted By: Bobo23
Decaying rubber scum. Sounds like a punk rock band.

I don't know how else to describe it. The hose is fuel resistant but after years it begins to break down somewhat.
On older cars ethanol laced fuels accelerates the deterioration faster.
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