W123 Slow until reved at least once
 

Hi I have a 300d Turbo that is really slow to rev until it's been reved at least once to 3k or so.

I mean when I hit the accel to the floor it takes about 15 seconds for the RPM's to get to 3k but once it hits that point it's quick every time there-after.

Weird I have to rev it once and the problems gone for the rest of the time the engine is running.

It doesn't miss or have a rough idle or any problems other than being slow to hit the 3k mark.

Any clues?

Is there excessive black smoke out the tailpipe during the wait? I suspect not but it may be an important clue for others. I do not have a clue myself as this is generally a gas engine problem. Others may have dealt with it on diesels.

Is it a California model?

No it's regular Federal. I think it could be the ALDA??? I don't know

could this be the turbo spooling up and then its all nice and lubricated?