On May 23, 6:24 am, philthy <dbri...@cac.net> wrote:
> 02 sensors and map sensors come to mind first
>
>
>
> kevin.do...@ns.sympatico.ca wrote:
> > For those of you who like diagnosing strange problems I have a doozy
> > for you.
>
> > The symptoms are as follows: Very rich smelling exhaust, inside of
> > tailpipe VERY thickly coated with soot, badly carboned plugs.
>
> > I have checked the following: Manifold vacuum (20 ish in/Hg at idle in
> > gear), done an aceytelene test around the intake and throttle-body
> > gaskets/assemblys. The OBD system reports NO PROBLEMS, the mpg figures
> > are all over the map over the past 2 months I have gotten from 14 to
> > 33! mpg using the same brand/grade of fuel driving the same routes
> > every week. I have made NO changes to the vehicle WHAT SO EVER.
>
> > This has me stumped.
>
> > How about you.- Hide quoted text -
>
> - Show quoted text -

Get a gauge on the fuel rail (assuming your year has provisions for
this) and ensure that the supply/return paths are up to snuff.

On the other hand, if mine ever turned out 33 mpg, I'd let it do
whatever the hell it wants....

Jon