Literally anything that fits snugly? Off the top of my head: a pop rivet, a golf tee, an action figure lightsaber, a piece of sprue from a plastic model kit... Doesn't have to be fancy and there isn't a ton of pressure there.

-Rog

agreed that any short piece of fuel line plugged up works.
I used to purchase official plugs then realized even a vacuum plug from local
auto parts store, or a piece of that injector line plugged up works.
If you do not have some extra fuel line around, you will eventually when you
go to replace the lines.

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80 300D 340K Owned 30 yrs
83 300SD 440K Owned 9 yrs - Daily Driver 150mi/day
02 Z71 Suburban 117,000
15 Toyota Prius 2600 miles
00 Harley Sportster 24k
09 Yamaha R6
03 Ninja 250

If there is a dealer nearby, VW used them and likely Volvo. Good luck!!!

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"Rudeness is a weak man's imitation of strength" - Eric Hoffer

Best. Answer. Ever.

For the entire time I owned my '84 300D it had a stainless steel bolt in the end line. Never got around to changing it, mainly because it never leaked.

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1991 300D 2.5 "Rocinante"
2002 Golf TDI "Teen Spirit"
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1984 300D
1966 Mustang I6 3sp
1985 Mazda RX-7 GSLSE
1982 Toyota Supra
1977 Datsun 280z
1971 Datsun 240z