Q: 4T65E just replaced 08 Lucerne 3.8L, replaced plugs/wires/1 coil pack melted at #4 so replaced it now rough idle

asked by on November 12, 2017

Should I now replace the #4 and #1 plugs and wires because of the coil pack meltdown? I appreciate your help.

My car has 68000 miles.
My car has an automatic transmission.

The coil pack melts down for a reason and cause will need to be diagnosed what caused it. The most common cause is a short in the signal wire or excessive resistance in the plug wires or plugs. I recommend replacing plugs and wires and then if it still runs bad then check to see if coil is getting hot. If it is then the coil is shorting due to signal wire from computer is keeping the coil energised and overheating it. You may have a computer circuit fault and would need to have the wires checked for shorts or the computer may need replaced.

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