canoswagg2

I was getting misfires in a few cylinders,so i changed all the plugs and the ignition coils,now my car wont go over 40 whats some options

VegasES330

Do you have a check engine light? Have you checked for any codes from the ecu?
Autozone will check them for free. Start there, if you haven/t already.

milirx450h

One thing that happened to me on another car a few years back when I changed out all of the spark plugs was I found I had a cylinder that was obviously not firing. After assuming that I had done everything correctly and was at my wit's end I reluctantly took it in for someone else to look at it. They found that one of my BRAND NEW spark plugs was defective. If you have your old plugs, and it ain't too much work, try replacing the old plugs one at a time to see if that makes a difference. You might also look at the electrical connectors for your new ignition colis to make sure you got them fully seated.