Bucking broncos

[Dave Head <dhead@sundial.net>]

Symptoms...  
On the way home last night - drivin 65-70. Car starts bucking - same feeling
like overboost cutoff, except intermittent. Completely out of the blue - car
has been running good fer months.
Limped it home 15 miles - bucking intermittently at all speeds. 120 miles
into a tank of gas.
Pulled a few plugs today - looked good, replaced fuel filter. When I first
drove it today, it didn't act up for the first 3-4 miles or so. Shut car
off, went into auto store for 10 minutes. Came out - doing it again. Put old
dist cap and rotor one. No change. Drove 25 more miles at all speeds up to
80 - comes and goes.
Plugs are less than 5K miles old. Wires are one year old. Fool pump is 2.5
years, 60K miles old. Injectors unknown age.
Pump makes no unusual noises, possibly a bit quieter than usual. Fuel pump
relay 6 months old. Freq valve sounds fine.
I've semi discarded a bad gas theory as I was 120 miles into a tank, just
under 3/4 full. I fill it every other day and never go under 1/2 tank.
Leaning toward fuel pump even though its relatively new.

Any ideas...?

********************************AUDI FAN***********************************
                                   EMCM(SW) Dave Head  
87 5KCStq 221K miles                1.85 or so... bar 
    qcusa #3442           Oviedo, Florida     plate: STLTHTQ
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