Don't worry it's normal for diesels. If you're worried about power, make sure you've done the normal turbo tune up checks, like the pressure tube/banjo bolt from the intake to ALDA which gets clogged often, adjusting ALDA, making sure you've got a good clear intake path, etc. My SD was a slug most mornings under 15-20*F. I try not to drive it much in winter anymore.

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth