I have a pop tester and have done 3 sets of injectors so far (1 Mercedes and 2 VW's) . I always pop the injectors with the old nozzles first. All 3 sets were closely matched in pop pressures (within each set) and they all have only one shim in each injector. The new nozzles that were put in the 3 sets of injectors did not require any additional shims- they were all within spec with the original shim. Maybe I was just lucky that the nozzles I got were closely matched? Two sets were Monarks and one set was Bosch.

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
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