okay so ive had my 4runner for 2 months and I love it, but today in the morning i went to start it and it wouldnt turn over. I gave it a little gas and it fired up, but if i let of the gas completely the idle would go down to around 500rpm and the usual is about 2000rpm. Also the car started shaking badly. And the first couple time i started it up when i let off the gas it died!! Whats going on? Its never done this to me before!!! 
