Re: Starting Problem

[smarinel@Flint.Mines.Colorado.edu (Steve Marinello)]

>> It's the fuels...the volatility of the different "winter/oxygenated fuels
>> varies and some have significantly different characteristics, especially in
>> "warm" winter weather.  In my '83 TQC, I cannot run Phillips 66 during the
>> winter without having major cold start problems.
>
>Just how much do you think volatility varies anyway?  And how would
>this affect starting in "warm" winter weather, whatever that is?
>According to the Bosch handbook, volatility really only becomes a
>concern at very high temperatures where vapor lock could be a problem.  At
>any rate, it has a negligible effect on starting a cold engine.
>
>  Conoco gives me great
>> cold starts, but often pain in the *** warm starts.  It's just crapshoot
>> with each car having its preference based on its particular setup.  A lot
>> of it depends on whether it's ethanol or MTBE being added,among other
>> things.  
>
>Did you evaluate these fuels under identical operating conditions, e.g. 
>humidity, temperature and pressure, every time?
>
>What you seem to have is an engine in a very marginal state of tune, 
>and you are trying to blame this on gasolines.  If all this crap about
>the gas making cars hard to start were true, I would be seeing
>stranded motorists everywhere.
>
>> Try a few different top line gasolines.  Unfortunately, Chevron,
>> Exxon and Shell aren't around here in Denver anymore and their are few
>> Amoco stations near where I live.  Exxon used to be the best for me
>
>With few exceptions, e.g. Amoco, all grades of gasoline are commodity
>items.  There is absolutely no guarantee as to who's gas you'll get no
>matter what station you go to.
>
>--------------------------------------------------------------------
>John Greenstreet, Senior Engineer           (jgreenst@motown.ge.com)
>Martin Marietta Government Electronic Systems    Moorestown NJ 08057
>WPI Class of '75, Temple Class of '94

John:

The Bosch manual probably never considered our oxygenated fuels.  These
fuels are designed with higher "low temp" volatility in order to achieve
cleaner burning, expecially before the engine warms up completely.  That's
why these fuels often have such a strong smell on warmer days during the
winter driving period.

And, yes, I did evaluate the different fuels under approximately identical
conditions over a couple of winter seasons.  of course, the actual
composition can vary from year to year or tank to tank.  And my TQC is not
in need of a tune-up.  However, you're right about the commodity item
aspects of most gasolines.  You've got a limited number of refineries
producing the base gas, with special or proprietary additives being put in
either at the refinery, the bulk terminal or at the station.  In fact, in
the Denver area, the additive (ethanol or MTBE) can vary between brand
stations located less than a mile apart.  Just another parameter of
confusion and uncertainty.

Steve