Doug Schwarz wrote:
> "Jim M" <jbmoore3nospamnospamast.net> wrote:
> > >> Doug Schwarz wrote:
> >
> > > Any other thoughts, anyone?
> > >
> > Have you checked the inside of the distributor cap to see if it's clean.
> > Many of the non-turbo's (including my 1995 900S) have a leaky distributor
> > shaft seal. Mine's done it for years. It's only a little oil that gets by,
> > but every a few months it accumulates and I notice the idle is less smooth
> > and it's more difficult to start off from a stop(5sp-M/T). Lately I just
> > pull and clean the cap at every oil change (3k miles) and that works fine.
>
>
> Thanks for the suggestion. As it so happens I have just come in from
> having done exactly that! Yes, there was some oil in there, but not
> very much. I cleaned it up and took a short test drive, but the
> vibration was still present.
>
> I visually inspected all the HT wires and they look to be in quite good
> shape. I'll have to look at the service records to see when they were
> last replaced. I realize that you can't tell if they're faulty just by
> looking at the outside, but if they're new they're most likely okay.
Sometimes things just fail unexpectedly.
Plugs can develop degraded insualtion for example.
I had a Vauxhall once that behaved a bit like your Saab. The problem turned out
to be a hairline crack in the distributor cap.
Graham