2004 S4 Avant - intermittent starting problems
 

The car:
2004 S4 Avant, 80K miles

The issue:
Car fires immediately after sitting overnight or for more than ~1.5 hours after previous use
Car won't fire immediately after shutdown (ie. stop on the way home for gas)
Car will shut down randomly at stoplights or whenever NOT under any load. This is independent of RPMs (as far as I can tell...I've sat at lights holding 1200 RPM and it has still shut down)
Car will not re-fire after said stoplight incidences (for at least 1 hr)
Car WILL bump start every time with sufficient velocity (includes reverse.)

The owner:
Is bummed!

Thoughts?

The fact that it starts every morning and will bu

Mine did this for about a year becoming more frequent recently. Turned out to be the Engine Speed Sensor (analogous to a cam position sensor). It tells the ECU how fast the engine is turning and without it, the car won't start. Again, that VAGCOM download noted in your other thread will confirm this. Take a look at a recent thread on the subject and note the associated codes numbers: 16705 / P0321 and 16706 / P0322.

https://www.audiworld.com/forums/sho...e+speed+sensor

Have the DTC (diagnostic Trouble codes) read from the computer and go from there