You need to find the correct opening pressure and reset the opening pressure.

The Injector spray has to push against the density of the density of the compressed Air inside of the Cylinder.

On the Turbo Engine when the Turbo kicks in even more Air is compressed in the Cylinder and that Air is denser than the non-turbo Engine; so the opening pressure on the Turboed Engines is set higher in order for the Injector spray to penatrate the denser Air better.

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84 300D, 82 Volvo 244Gl Diesel