Tech Tip

[Dana <dasquestbox@xxxxxxxxxx>]

The latest Bavarian Autosport (BAS) catalog (fall & winter 1998-1999)
has an excellent tech tip on pg. 65 that gives a warning against topping
off the fuel when filling the tank.  If your car has some of the
symptoms below and you haven't been able to locate the cause, they
recommend replacing the charcoal canister.

"When you fill the fuel right up into the filler neck you are allowing
fuel to enter the fuel vapor recovery system.  This will contaminate the
charcoal vapor recovery canister with raw fuel and effectively clog the
canister and, hence the tank vent system.  Symptoms include: premature
fuel pump failure, hard starting when warm, loss of power after driving
for a while and premature fuel pressure regulator failure."

My 1984 E28 seemed to lose power after warm up and I hadn't been able to
determine the problem after trying for over a year.  After reading the
BAS tech tip, I immediately went out and simply disconnected the fuel
vapor line from vapor recovery canister (right side engine compartment
below the washer fluid reservoir) and Voila!  No more power loss after
warm-up.  Now the car runs GREAT all the time, not just after cold
starts.  The "butt dyno" effect is like putting in a performance chip
but without the cost.

Even if none of the symptoms above are apparent, it may be a good idea
to test your system by disconnecting the fuel vent line at the charcoal
canister, especially if your bimmer is over ten years old or has high
miles.  I'll (eventually) buy a replacement canister from BAS ($34.95)
as a way of saying thanks for the tip.  But for now, I'm just enjoying
the ride.  If this info helps solve anyone else's problem, a thankful
reply will be enough.

        Bavarian Autosport
        www.bavauto.com
        1-800-535-2002

D.A. Smith
Indianapolis

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