Did you say "low" or "high" revs??
9,000 (nine thousand) is very HIGH revs for a car (diesel or petrol)!!
I assume that it is a "typo" & you meant 900 (nine hundred)!!
IMHO, this is about the practical lower limit for a lot of cars (diesel or petrol).
Although diesel engines usually are regarded a lower-revving, you have to remember that modern diesels have been developed for modern cars & are a bit more highly tuned than good old-fashion "Tractor-Engines"!
HTH
Regards, John
Could you help.
> I have a 406 T reg HDI 90.
> At about 9000 revs in neutral the car judders like a petrol would with a
> dodgy spark plug.
> Any revs under 9000 or over and it goes away.
> I use additive for cleaning the injectors regular, but unsure what it could
> be.
>
> Any ideas.
>
>
> Thanks in advance
>
> Richard
>
>