Sounds like a low voltage or weak coil issue.
Make sure all the grounds are good and find out what the ohm reading on your specific coil is and test it.
Chk your batter voltage while the car is running and while you turn your lights on.
This will give you an indication of whats going on.
Can't stress enough to make SURE the grounds for the ECU as well as the engine to body are in nice clean contact.
Add the alternator ground to that list.
You can test for voltage with a meter between the alt case and the battery negative (should be zero)
