I was taught about battery voltage having an effect on injector operation during my schooling, but here's a couple articles I found online that also advise to insure the battery is in good condition.

Bottom line: when your battery voltage decreases (such as when cranking) your injectors take longer to open and fuel injector latency increases.

Theory: An Injector Model « Moates Support

Test your battery to make sure it's in optimum working condition. If your battery's too weak, it can affect your fuel injector's performance and alter the outcome of your emissions test.

How to Pass Emissions Testing | eHow.com

 

You know.. I've been feeling like I'm having fueling problems in the Camaro... and it takes a little hold to start in the mornings...

 

My experience with coils is that the factory ones rarely go bad. And these days, I'd rather a salvage yard coil then a aftermarket one from the parts store. The few times I've had coils fail, one of them was infact from the parts store.

 

BWD= Broken When Delivered
(experience talking)

-P