Debris can get into the idle air control valve. This will restrict the air flow into the engine, causing idle speed and/or stalling when cold. The valve can be cleaned or replaced to correct this concern.
Car Problem Reports
Toyota Avalon Debris in Idle Air Control Valve May Cause Engine Problems
Toyota Avalon Problem
Engine Affected: 3.0L V6
Average Mileage: 163,611 mi (142,000 mi - 180,000 mi)
Visitor, 2001 Toyota Avalon, 3.0L V6, 175,000 mi
It is very intermittent on low idle and dies. Haven't solved yet been living with problem for several months.
Idle was erratic, sometimes racing, sometimes it wouldn't idle without pressing throttle. Had mechanic clean the IAC valve and fixed the problem.
Visitor, 2001 Toyota Avalon, 3.0L V6, 157,444 mi
Car started, but stalled immediately revs dropped very low. Replaced ICV ($400 plus labor) and car is fine.
Visitor, 1999 Toyota Avalon, 3.0L V6
80% of the time my care idles low are dies, have to double peddle to go.