My car has almost 150k miles and I was thinking of changing the coils as part of maintainence. It runs pretty good, has a slight miss every now and then but overall runs good. I was just wondering if I should spend the money, or just leave alone unless there is a problem.

Thanks in advance guys.

What kind of car is this? Gas or Diesel?

What kind of car is this? Gas or Diesel?

Uhh, I'm just going out on a limb here, but I'd take a wild guess and say it's probably a gasser...:p:

Yes, it is a gas. 3.8 bonneville

"Ignition coil's work or they don't."
If you have a miss every now and than, it won't be your coil. It could be a ton of things, but more likely to be carbon built up or some not so good fuel.
When was the last time you changed your spark pluggs and or ignition wires?
Ign. wires can cause an intermittant miss fire, specially on colder days and when the hymitety is higher than normal.
I was a technician for more than 25 years, so this is not smoke comeing out of some place down south.

Yes, it is a gas. 3.8 bonneville

Just a suggestion, I think you may want to post your question in a Bonneville forum somewhere on the cyberspace. You probably can google it. You will get some general advice in a DIESEL forum by some mechanics that happens to be here but it won't be specific to your car.
Most of us drive gas too but not necessarily a Bonneville.

If I am wrong, forgive me.