Well the thermostat was a new, german built unit. Yes, i believe it's
defective. I plan to install a known good used one soon.
I tried cardboard infront of the radiator and sure enough, the temp still
dives at highway speeds. Very odd.
I will be unplugging the o2 sensor and seeing if that makes it run like
crap on my next drive of any substance.
I have put some injector cleaner in the gas, and it has been pointed out to
me that the starting issue could be a leaking injector, which would also
account for the decreased fuel mileage. I plan to send a spare set off to
the wizards for testing/calibrating.

-Craig

On Sun, Feb 3, 2013 at 12:13 PM, Dennis Haynes <d23haynes57@hotmail.com>wrote:

> I know it's not Friday but how about doing some real honest to goodness
> trouble shooting? Seriously! It is easy enough to test the O2 sensor to
> determine if you are getting proper mixture control. Also, if the engine
> temperature is falling at highway speed you may be going into open loop
> control or even worse warm up enrichment. In addition the lower temp also
> means less efficiency and increased oil viscosity.  Four screws, change the
> t-stat. Keep in mind that extended warm up time, idling, additional
> headlight and heater fan use all affect fuel economy. Automatics and
> Syncros
> take a real hit for winter operation.
>
> Dennis
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Craig Cowan
> Sent: Saturday, February 02, 2013 3:19 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: TERRIBLE GAS MILEAGE/Running Cold?
>
> Well, i've gotten a step closer to solving the running issues, i believe.
> Yesterday i found the temp gauge will still dive above 60mph, and it was
> warmer (25*F or so?), but i think the issue is bigger than just a
> faulty/weird thermostat. I think my 8mpg running is in part coming from
> terrible grounds.
> When I first built this bus, for whatever reason I seem to have forgot to
> deal with the grounds?
> My chronically slow starting condition suddenly made since, and i dove into
> the engine bay to find the braided cable snapped off in my hand, and all
> the
> ring terminals looked like crap.
> I cleaned up some of the ring terminals and replaced the ends of a few
> others. I put a 4 gauge grounding cable from the engine to the body and
> from
> the starter motor's lower bolt to the body.
> My starting is still screwed up, but seems improved.
> I can't wait to see how this effected fuel economy. I imagine the entire
> fuel injection system was reading poorly if the grounds weren't sound.
> Hopefully my messing with wires didn't awaken any new beasts.....
>
> We shall see.
>
> -Craig
>
>
> On Fri, Jan 25, 2013 at 11:52 AM, Stuart MacMillan
> <stuartmacm@gmail.com>wrote:
>
> > I've had a surprising number of aftermarket thermostats not work
> > properly over the years.  Quality control is non-existent on some of
> these
> parts.
> > Your high speed temp drop points to the T stat not cycling or opening
> > too far at speed, which is pumping the coolant through the valve at
> higher
> > pressure and perhaps holding it fully open.   T stats are constantly
> > adjusting, or should be, to keep the engine temp constant.
> >
> > Change it to what Dennis recommends.
> >
> > Stuart
> > '85 Westy
> >
> > -----Original Message-----
> > From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
> > Behalf Of Craig Cowan
> > Sent: Thursday, January 24, 2013 12:00 PM
> > To: vanagon@GERRY.VANAGON.COM
> > Subject: Re: TERRIBLE GAS MILEAGE/Running Cold?
> >
> > Hmm.... It is an aftermarket thermostat but stock temp and speced for
> > the Vanagon. It was stamped Germany and the club installed it, getting
> > the seal of approval by several members.
> > It also did operate as expected, and it works fine up to 60mph.
> > Odd....
> >
> > -craig
> >
> > On Jan 24, 2013, at 2:18 PM, David Milo <dellaone@GMAIL.COM> wrote:
> >
> > > From a post on 12/12/12 from Dennis Haynes: What are you referring
> > > to as high temperature? The stock Thermostat rating is 87C, (188F).
> > > That is plenty and should be used all year. From experience, the
> > > most consistent acting and best response are the ones from the dealer.
> > > (???). Of the features of the part the top control disc has a rubber
> > > gasket to ensure no leak by when it is closed. Next choice would be
> > > the Wahler, (German). I have had some Mehle that fit but they may be
> > coming from unknown sources.
> > > If you do go to a parts store, almost all will sell you the wrong
> > > stat. The lower disc will be the wrong diameter. If the listing
> > > includes some Audi or other vehicles it is wrong.
> > > The confusion comes from the practice that T-stats get listed for
> > > vehicles based on just a few specifications. Usually the top housing
> > > diameter is the key. Vlave types, bypasses, bleeds, lengths and
> > > other
> > features get lost.
> > > This is a real problem even in American vehicles, trucks, RV's that
> > > need stats with more flow and thus use a different design such as
> > > umbrella instead of disc. The wrong stat may jam partly open and/or
> > > not open far enough for proper cooling.
> > >
> > > Dave Milo
> > >
> > > On Thu, Jan 24, 2013 at 2:10 PM, David Milo <dellaone@gmail.com>
> wrote:
> > >
> > >> Aftermarket thermostat? Could be malfunctioning. I have read many
> > >> times from Dennis Haynes that most aftermarket thermostats do not
> > >> fit or operate properly. Extreme conditions could exacerbate that.
> > >>
> > >> Dave Milo
> > >>
> > >> On Thu, Jan 24, 2013 at 1:23 PM, Jeff Lincoln <magikvw@gmail.com>
> > wrote:
> > >>
> > >>> I am reluctant to reply to this Craig but is it possible, even at
> > >>> 15deg, that it's just because it's cold?
> > >>>
> > >>> Gertie runs the temp gauge dead on center - consistantly, until
> > >>> this week
> > >>> -
> > >>> it's been very cold here this week ranging from about 2deg to 15
> > >>> or so - the needle is running at about 1/4 - 1/3 and cabin heat is
> > >>> there but not as it was. Again, I could be talking out my backside
> > >>> but it sort of made sense to me - thinking about trying the
> > >>> cardboard trick myself just to see if it helps.
> > >>>
> > >>>
> > >>>
> > >>> --
> > >>> Thanks,
> > >>>
> > >>> Jeff
> > >>> '85 GL (Gertie)
> > >>> '78 Bus (Melissa) Patty's Bus
> > >>
> > >>
> >
> >
>