[V6-12v] Non-Starting Car

[Casimiro Izquierdo]

I have 1995 Audi 90S that is giving me starting problems.  When the car is cold it will start OK.  However if I drive it for about 10 minutes and then turn it off for about another 10 minutes, it will not start.  The car will crank up but it will not engage.  Once it did start by pushing it, but another time I was not successful at doing it - maybe because I was not going very fast and the car did not catch.

The check engine light has been coming on and off for the last 5 years.  It comes on after driving it for about 20 minutes and then sometimes it goes out.  It will not return after the car is turned off and then on again.  

Does anyone know what could be wrong with this car?  It has 144,000 miles.

Thank you.

cai