7mm
I had to get a 7mm box wrench in order to change my #7 cylinder coil. took a while there's no room under the fuel rail for a socket and wrench.
there is a small bolt that holds down the coil for each cylinder.... It has a 7 or 8 mm head on it and is longer than I think it should be.... probably 1.5 inches or so, so be patient taking it off. On the passenger side, the bolt is towards the outside of the engine in front of the coil itself...
Easy job. Depends on the specific coil though. Just locate the coil wires atop the coil itself and unplug the clip/wire. You'll need a ten millimeter socket wrench and an extension to get at the ten mm bolt that holds the coil in. once you get the bolt out, you just grab that jewel with your fingers or a pair of pliers and pull it out.
disconect the coil and remove the 7mm bolt that holds down the coil, remove the coil then plug.
Take off the plastic engine cover , take out the bolt that hold the coil , take out the coil.
if the coil is on the distributor cap,remove cover then disconnect wires from the coil and remove coil. if coil is on engine then loosen the bolt and remove from coil mount
The coil packs are low on the engine block, behind the radiator fan.
You have to remove the plastic cover on top of the engine and you will see 4 ignition coils with snap plugs on them, pull out on the little black tab and gently disconnect the snap plug. Remove the wires from the coil and the one bolt that holds the ignition coil down. Then just pull up on the ignition coil and the plugs are under them straight down the center of the engine..
Replace the coil.
The problem is with the coil or coil pack. There is a large bolt through the coil that goes into the block it will sometimes get hot when it does the engine will not run.
Unplug the connector on the base of the coil. Remove the bolt that holds the coil in place. Pull the coil and spark plug boot off the spark plug. Install new coil in reverse order.
A diagram for a 2001 Chevy impala 3.4L engine & coil pack firing order
There are ( 6 ) individual coils for your Coil On Plug ( C.O.P. ) ignition system on your 3.0 liter V6 engine