Misfire and/or Check Engine Light Due To Failed Ignition Coil on Cadillac DeVille DTS

Problem Description and Possible Solution

An ignition coil may fail causing one of the cylinders to misfire. Each of the two banks of cylinders has its own coil assembly. If one ignition coil fails the coil assembly for the corresponding cylinder bank must be replaced.

Problem Data
RepairPal Verified
Average mileage: 109,293 (82,347–160,000)
5 model years affected: 2001, 2002, 2003, 2004, more2005
18 people reported this problem
Viewing 1 - 10 of 10 comments
Car idles rough and check engine light is on and sometimes flashes. Worse when engine warms up but idles rough even when cold. Diagnostic check shows P0300 and 303 codes which indicates a misfiring in the #3 cylinder. I haven't troubleshot it any further. I don't want to drive it as it could do damage to the catylitic converter when the check engine light flashes.
I'm having that same issue now, i was told by a mechanic that's it's the 6th cylinder that's having the issue.. My question is, is this bank of coils in a reasonable spot to work on.. I've fixed my door actuator n Chg oil, etc, but I'm kinda nervous bout messing the Northstar, any help would b greatly appreciated.. If it's not to difficult, I'd like to try rather than pay 620 to get it fixed
AT IDLE CAR SHAKING SEEMS LIKE MISFIRE COULD IT BE RUBBER BOOT BETWEEN THROTTLE BODY ? OR DO YOU THINK IT'S DEFFENTLY IGNITION COIL ON ONE OF THE CYLINDERS .
My vehicle was doing fine. I started it up one morning, and the check egine light came on,along with misfire and vibration. the diagnosis is misfire in # 4 cylinder. I am parking it until it can be repaired.
Replaced front and back coil and plugs
Ignition coils misfire. Smell rotten eggs (Unburned Fuel)Need to replace ignition coils and catalytic converter.
Problem started around 98000 mi. Green Chevy/Cadillac diagnosed and repaired the problem quickly
misfire on one clyder
Bad back ignition coil
replaced the ignition coil with a new one from amazon.com. Cheapest prices around.