Q: Car starts but runs uneven, ignition module and coils replaced, battery fairly new

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vehicle starts with some slight hesitation, runs very rough. Similar Situation 6 months ago and an ignition module and coil fixed it. 2 more coils now changed and back to square one. Runs rougher with trans engaged, little movement possible. Battery is 2 years old.

My car has 204000 miles.
My car has an automatic transmission.

Hello, thanks for writing in about your 2003 Pontiac Bonneville. Make sure all of the connections the the ignition module are tight. If one of the wires are loose you will have a rough running engine. I’m sure its something as a connection problem. Your battery would not be the reason it doesn’t run good. If you’re unable to pinpoint the issue yourself, consider YourMechanic, as one of our mobile technicians can come to your home or office to diagnose your rough running condition firsthand.

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