i have a 03 bonniville that shits off while driving it
Shame on it for doing that, and in public too. LOL. Sorry couldn't resist. Anyway the most common failures are crank and cam sensors, ignition control module, and the coils themselves. You didn't state the engine so I assume it is the normal 3800. As yours seem to do what a bad ignition module does I would replace it first, unfortunately this is the most expensive part. Use a good quality replacement like a NAPA or OEM, But you will find OEM to be much higher than NAPA's. You may want to do a code check before starting any of this just to make sure there are no underlying problems.
If it "shits" off while driving I would install a car diaper to keep the brown matter off of other cars on the roadway. Many times proof- reading your post will help keep annoying people like me from making snarky remarks to your post. Heck, sometimes that doesn't even help.
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