Has anyone had a problem with a 2001 stalling? It usually happens when I start it (not all the time). It starts fine, revs up a bit and then drops down to 500 or 600 rpm (normally around 800). Sometimes it will just die after that and sometimes not. When I try to take off with it, it has absoutely no throttle response. I've cleaned the inside of the throttle body, run a few bottles of injector cleaner through it, put in a new set of iridium plugs, and it still occasionally does it. No codes in the computer are left. Any ideas or solutions?