please help

So, recently on cold starts my engine makes a loud noise that I could only guess is piston slap. Correct me if I am wrong, but it is a constant almost slapping or knocking sound for the first 20 seconds and then goes away until I let my car sit for 4 or 5 hours and start it again. I have...

I have thought for a while that my car felt very unstable in the rear, under hard acceleration or swift lane changes I get a substantial amount of rocking or wagging in the rear suspension. I had chalked it up to me being over critical until I let a friend drive my car while I drove along side...