rough start
 

Every couple of times I start my enging my entire car will shake horribly, and my RPM's will be lower than normal and also the exaust will not make its normal noise, it will also pump out a lot of blue smoke from the exaust, usually this only happens from about 10 seconds to a minute but i am very confused about what is going on with it any and all sugestions please. She has 62K on the clock right now.
Thanks
TONY