You may have two seperate problems occuring at the same time. First I will offer this for the engine light and misfire. There are a few things which can cause the misfire some cheaper than others but here we go.
#1 Improper or damaged spark plugs.
#2 Fuel injection system faulty
#3 EGR valve not funtioning properly
#4 Vacuum leak
#5 Problem with the engine control system (expensive)
These are a few good places to start looking.
The other noise problem sounds more like a bad tire that could have seperated causing the tire to become out of round making the noise and the shaking of the car. It could also be tire balance but most likely you have a bad tire. The shaking could possibly be causing the engine to make a false diagnosis of misfire due to the sensor being shaken so violently causeing it to misread the virbration.
My first choice would be to get the tires checked out first then reset the computer by disconnecting the batt for ten minutes and then redrive the car and see if the problem comes back (this is just if there is a bad tire). If it comes back after checking the tires with no problem then look into the other items I have listed.
Hope this helps!MORT
Thursday, December 4th, 2008 AT 8:23 PM