Does a defective coil on the spark plug for a 05 Deville not send a check engine error or should it? everything on the car shows good on the instrument panel although at idle at a stop sign the car has a bumb/jerk feeling like it is misfiring on a cylinder. I have tried a new fuel filter, air filter and new plugs to avail- Any advice would be helpful.

Thanks

 

Problem with misfire issue was the coil ignition assembly that is connected to the spark plugs on the front of the motor. Replaced it and car feels like new- Cost for part was roughly $270.

This symptom was bumping and jerking at idle while at stop sign- Process to replace was a short amount of time- It did require removing the Engine cover and the radiator cover to expose the coil ignition bolts (4 total) 10mm wrench used.