a dual rubber o-ring seal on each injector. I've never changed one but recall seeing it on my All-Data CD-ROM.

Don't think there is any 'plastic' except for the "electric plug" that carries the signal to turn the injectors on, from LH-SFI module.

Also they are mounted on a fuel rail that goes around the engine, so it may have to be removed accounting for the 'all-must-be removed' statement from your tech.

I'll check with my tech and let you know what he says.

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Regards . . . . JimF
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'94 S500 Cpe

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