My Toyota Sienna 2002 van has been stalling when I stop off and on for about 2 weeks. Most times it starts up again and continues to run. I can go days and it doesn’t happen then yesterday it happened 7 times in the course of 10 minutes. I’ve had it connected to a computer diagnostic system three times, couldn’t find any error messages.
The problem might be with Idle Air Control valve.
http://www.rockauto.com/catalog/moreinfo.php?pk=319854&cc=1167410
The IAC valve controls the engine idle speed whenever you release the gas pedal.
It could be that the IAC valve needs cleaning along with the throttle body idle air port, or the IAC valve itself is faulty.
Tester
Testers link is not showing the correct part but IAC failures are common and will not set codes.