Engine Performance problem
1990 Audi 90 Front Wheel Drive Automatic 170, 00 miles
1990 Audi 90 10 valve 5 cyl, car starts perfect when cold, when parked for longer than 20 minutes it will start right up but stumbles, coughs, and has a very unresponsive accelerator pedal, keeping it floored will slowly raise rpm and keep it running, it will do this for around 30 seconds and then clears and revs cleanly. Throttle while driving has flat spots in it and car seems doggy and underpowered. This is a new to us car, new cap, rotor, plugs, fuel filter, no vacuum leaks detected with ether spryaed while running.