I got the same problem with my 2000LS auto too. Some kind of flaw with the tranny. Hav`nt had the time to put it in the dealer yet. Still under warranty. Another thing I notice is when I'm driving and I let off the gas, the car jerks. Same when I apply gas. Wierd huh? I'll let you know what the dealer says when I get it to them. Like freakn 30 miles away.