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From: rctracy@uokvax.UUCP
Newsgroups: net.auto
Subject: Re: 2002 BMW Strange Stalling Problem - (nf)
Message-ID: <6598@uiucdcs.UUCP>
Date: Wed, 4-Apr-84 01:32:19 EST
Article-I.D.: uiucdcs.6598
Posted: Wed Apr  4 01:32:19 1984
Date-Received: Fri, 6-Apr-84 00:45:27 EST
Lines: 49

#R:teklabs:-278700:uokvax:1100016:000:1954
uokvax!rctracy    Apr  2 12:32:00 1984

/***** uokvax:net.auto / teklabs!donch /  7:25 am  Mar 30, 1984 */
...  It occurs on the level, uphill, downhill, high or low altitudes,
usually during our rare and precious vacations, and almost always
after an hour or more of continuous highway driving...

Any thoughts greatly appreciated.

Don Chitwood
Tektronix, Inc.
Imaging Research.
teklabs!donch   
/* ---------- */

It sounds an awful lot like vapor lock to me.  I wouldn't be surprised
if the problem gets worse during warm weather, although how well your
engine compartment retains heat might make the effects of ambient air
temperature negligible.  I'll also hazard a guess that in-town driving
after a while on the highway is not a pleasant proposition...  Heat
buildup due to lack of airflow at slower speeds compounds the problem.
Driving with the throttle WFO (i.e., fast :-) would tend to clear the
condition since the fuel would be flowing through the lines fast
enough to keep it from vaporizing.  I have a station wagon that
exhibited the above behavior, and as long as I drove >= 90 mph, no
problem!

Three rememdies suggest themselves:

(1)  Insulate the fuel system from potential sources of heat.
     Granted, aluminum foil looks attrocious, but it has been known
     to work.
(2)  Increase under-hood ventilation (assuming the problem is heat
     pick up from this area, and not from the road).  I've seen
     nicely fabricated air diverters installed which do a wonderful
     job of cooling off carb fuel bowls, lines, etc.
(3)  Install an electric fuel pump near the gas tank end of the
     fuel line (so that the pump is pushing the fuel through the
     fuel line instead of pulling it through).  This will maintain
     pressure on the fuel in the line, and help prevent vapor lock.

Hope this helps.
(Solution 3 was what I ended up using for the station wagon, with
completely satisfactory results.)

		Bob Tracy
		AT&T Technologies, Inc.
		...!ctvax!uokvax!rctracy