OT - b3 16v passat issues

[amalventano at sc.rr.com (Allyn)]

Fellow listers,

(this is one of those cathy type emails - beware. issues at bottom of email 
for those willing to lend a tech assist)

    so i drag the whole family down to kings bay, GA today to check out / 
put an offer on a house. i also dragged dave winchell (red 16v) down with 
me. its easy, as he lives riding in the rieger. after a 3 hour drive, we 
arrive and check out the house. dave goes into 'appraiser mode' and gives 
the place a thorough once-over as i show the house to the wife. we all head 
over to the agents office to write up the offer. sandei decides to go 
straight home - the 3 kids are tired, and they are all in her passat.

    shortly after paperwork is signed and me and dave hit the highway, 
sandei calls - the passat is acting 'stuttery', but holding speed. we're 
about an hour behind her. i coax the rieger into light-speed to close the 
gap. 10 minutes later, sandei calls again - from the side of the road. 
great... 10 more minutes pass - called again - she is back on the road. says 
she is going to a gas station to add 10 gallons and some additive (in case 
of possible bad gas). 10 minutes later - another call - on side of road 
again. the cycle repeats a few times. turns out the passat only runs for 
about 10 minutes at a time then dies off.

    dave and i pick up some nylon rope (couldnt find tow straps anywhere), 
and eventually catch up with sandei - now on the side of the road for good. 
i give her a quick brief on what to do while being towed 10 feet behind a 
scirocco at 60 MPH, tie the cars up, and off we go. after a few phone calls 
to calm the wife down (she initially looked like she was in labor, i swear), 
we get a good pace and go the remaining 100 miles or so to get back home.

ok, now for the issues, as interpreted/translated from the wife:
- throughout all of this - engine temp was normal
- bucked very slightly intermittently. hitting gas harder only resulted in 
engine choking out completely.
- 30 minutes later, bucking got worse, eventually had to pull over.
- once pulled over, turning off ignition was followed by a few seconds of 
diesel action.
- wait 10 minutes, start 'er up, purrs like kitten, drives fine (even under 
hard acceleration).
- ~10 minutes into driving, bucking cycle repeats, along with the diesel 
action on shutdown.
- went slightly further between bucking events - with heat blasting.

my initial guesses:
- i suspect its bucking due to fuel being way too rich for some reason
- likely an electrical issue, as the car drives fine once its cooled down a 
bit. it appears to be an 'on/off' type of problem.

issues i expect while troubleshooting tomorrow:
- i may not be able to get the engine hot enough from merely idling to 
recreate the problem - as the problem was happening while going highway 
speeds. (i really done want to be that mechanic guy hanging under the 
truck - you know - in those commercials)

anyhow, please shed any past experiences / advice. i'm totally sucking for 
ideas at this point, and i need to have any possible info that might help me 
get this thing reliable again. its the family car. its gotta be reliable ya 
know :)

well... reliable until i can get a TDI to throw in there.

thx in advance
Al

Allyn Malventano, ETC(SS), USN
87 Rieger Scirocco GTO 2.0 16v (daily driver, 200k, rocco #6)
86 Kamei Twin 16V Turbo Scirocco GTX (30% complete, rocco #7)
86.5 Occo 16v Trailer (rocco #8)
90 Passat GL 16V (the wifes POS daily, 200k)