If as the last post said is not the problem the next step would be to check the wiring to the two coils that are not firing also is the engine light on for a Misfire code there are three wires going to each coil you should have 12volts on one wire the other wire should be ground and the last wire is the driver output from the computer check all the wiring it is possible that two drivers are bad in the computer that would not give you spark to the coils but check the wiring also see if there is any other codes in the computer like a cam or crank code. If you need the wire numbers to the computer get back to me and l will look them up.