If it has been well maintained, no problem.
most likely misfiring cylinder(s) and/or worn engine mounts.
Safe yes, smart no. You could very easily ruin the O2 sensor and the Catalytic Converter which are quite expensive.
You can but it is not a good idea. If your engine is misfiring then unburnt fuel will enter the exhaust. This will damage the O2 sensor and eventually destroy the catalytic converter costing you big time. Stop driving the car until you can have it repaired.
A flashing check engine light is an indicator of a serious misfire (usually more than one cylinder or consistent misfiring of a single cylinder). Have your OBDII codes read at auto zone or the like. They can tell you atleast what cylinders etc. are misfiring. This indicates a serious problem with the emissions system. The owners manual states that if the check engine light is flashing, do not drive the car!
it is safe to drive slower because you could get in a car accident if you drive really fast
NO! Depends on your definition of safe?
the only way I've found is to hook it to a computer and see which cyliinder has been misfiring. Once you know which cylinder is misfiring, swap the coil of that cylinder with a known good cylinder, if the misfire follows to the other cylinder you have a dead coil. Coil 8 on the 8 cyl models has a TSB published that requires to get some special seal to keep water from leaking down and shorting coils. The last time I check the seal kit was around $50
The driver is responsible for the condition of the car and the safety of passengers. It it is not safe to drive, don't.
CHECK WIRE
Depends on your definition of safe.
Yes