I am looking for someone who has shims for 603 injectors. I pop tested 4 injectors at around 200 psi, 1 at 195 psi, and 1 at 180 psi.

The shim on the 180 psi measures 11.4mm x 1.0mm. I am thinking that a 1.2mm should work, or narrow shims.

Is there a source for them that doesn't require a bulk purchase?

Not sure what or how you're measuring what you're doing but "injector" pop pressures should be in the 135 Bar(1957 psi) range for the 603 engine's injection.

Contact Greazzer he's the injector man...

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The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
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both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

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