Rubber fuel line fungus/mold/crud

One of the two fuel lines near the throttle body has this whitish/greyish crud growing on it. I wiped it off last year but it's back. I wiped it off again with a Clorox wipe but I am wondering if anyone knows what it is (fungus? mold?) and if the line should be replaced. No smell of gas or any leaks/cracks visible. Line is still pliable.

I only drive once a week so maybe the ethanol in the fuel is promoting fungal growth due to moisture in the fuel?

 

Pretty sure that's a vacuum line not a fuel line not that that matters in this case? Maybe a new hose altogether? If its just a vacuum line you could replaced with silicone (unless it carries fuel vapors).

 

No. It's a fuel line. You can see where they attach to the fuel rail for the injectors.

 

Maybe its the fuel return line. The actual pressure line wouldn't use spring band clamps and in your picture the one on the right doesnt. The line designated DTR CFP-III is high pressure fuel line. This leave the one with the fungus as the low pressure return. So yes both are fuel lines. And no idea on fungas, never seen this before. But since its a low pressure line it would be easy to replace with the right diameter low pressure fuel hose.

 

I assume its just from condensation of cooled fuel lines and the heat of the bay making for a place to grow.

Lots of ways to try and clean that up. Maybe engine cleaner. Or even distilled white vinegar supposedly works.

 

Maybe some Athlete’s Foot Cream