ply. grnd voyager, will not start, sparkplug, very weak spark?

Question

I replaced the coil with a new one, alternater is good,

Answer 1

There are several possibilities for your no-start.
If you have fuel (remove the little cap on the test-port and depress the little valve to see if you get pressure when cranking), you can eliminate this as a cause.
You have replaced the coil pack. If you are getting ANY spark, then the system is PROBABLY not the problem.
You could be looking at a possible loss of SYNC SIGNAL. The repair here would be to replace both the CAM and CRANK sensors.
It would probably be best to tow it to a repair facility and pay them their legitimate repair and diagnostics fee.

Answer 2

check ur battery..spark plugs..wires...ignition control module if ur car has one..when the last time u had a tune-up...does it crank ..if not..check starter too