Expert: Anthony Falcone - 10/13/2009

Question
well when the 1990 Eagle Talon Tsi Awd Starts it starts way high at 3000 rpms then drops to 1500 rpms and reves up and down like its surging

Answer
Jairek,
This problem is commonly referred to as idle surge.  Idle surge is the condition that occurs when something in the ECU idle speed feedback loop fails to operate as expected. Since the ECU is not quite as smart as you are and has a very microscopic view of its world, its behavior may seem very strange to you, but seem perfectly normal to the computer. The result is an idle speed that oscillates from ~1200-1500 RPM about 2 times a second and no error codes are ever displayed.  It's typically caused by a malfunctioning idle speed controller and/or bad O2 sensor.  You can have your mechanic inspect those components and replace if necessary.
Good luck!