My voltage drops sometimes from 14.0 to 10.9 then jumps back to 12.4, and when voltage drops it breaks up between 3500-4000 feels like it stalls a little and bogs barley. Could it be bad ground? Im thinking maybe coil packs? Help Anyone?

 

Check your battery leads, both positive and negative. Also, check all grounds as you mentioned.

 

Check your connection at your alternator as well.

 

They are all good? Should i go ahead and change the coil packs?

 

try running a 10 gauge wire form the positive battery terminal to the back of the alternator. the part with the nut on it.

 

I had major voltage issues recently, turned out to be a bad Optima battery.

Anthony

 

why would you change the coils if the prob is with the battery/alt or the associated wiring???

the coils are supposed to see 12+ volts how happy do you think old ones are when they get ~10v???

 

when i tap the breaks the lights dim also. I ran a 14 gauge wire from battery ground to ground for coil packs and starter harnes. Im gonna try that 10 gauge to back of alternator.

 

Thats why i changed my battery to a duralast.