Hello,

I have a 98 A8Q w/111k miles. Engine has been intermittently stopping since Monday after a fuel fillup whether idling or driving. Usually can restart immediately but not always. I put in a couple of cans of additive but no luck . I am replacing fuel filter on Sunday. No codes or CEL reported. It has been hot weather and I just replaced battery last Friday so can't rule out electrical. Battery charger took out cd changer in trunk. Bummer! Any thoughts?

 

Replaced fuel filter today. Car ran fine for about 20 miles and quit. Was able to restart. Let it sit for about half hour and drove it home (about 9 miles). Engine sputtered once while climbing a hill but did not quit. Engine died again right as I was pulling in to my driveway (Lucky day). I did a code scan and came up with a P0321 Ignition/Dist Engine Speed Input CKT Range/Perf code history. No CEL. A Google search shows several possible causes from a low battery (which was replaced a week ago) to a faulty crankshaft sensor to a faulty ECM. Any ideas on what to replace next?