I don't use a torque wrench either, but the recommended torque on installing injectors is about 50-60 lb-ft, basically pretty much all the torque you can generate with one hand with a 1-ft ratchet. Be sure to use new heat shields! The torque on the injector halves is about the same.

For a OM617 Turbo the pop pressure should be around 135 bar. If yours say 115 bar, those are not the original injector bodies and the injectors have likely been rebuilt. The nozzles you want are 240/ and you want to bring the pop pressures within 5 bar of each other.

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2004 VW Jetta TDI (manual)

Past MB's: '96 E300D, '83 240D, '82 300D, '87 300D, '87 420SEL