Montana,
I just recently put a custom exhaust on my LS and directly thereafter,
I realized I have a slight misfire, that doesn't throw a dash light all the time.
when I push it hard I can get it too flash and read the code immediatly.
from what I've learned here and as I understand it, a marginal coil problem,
is not always reported untill it fully gives out.
This is causing my LS to bog down a little during hard accelleration.
In other words, one of the coils is bad and causing a misfire,
the misfire if most likely constant but not noticable untill under WOT.
I'm not getting the full potential of the engines ability right now,
and if I ignore the problem and keep running it like this, I will
eventually need new CAT's as well, as the unburned fuel from the
misfire is getting into the CATs and burning up in there, causing clogging.
all this misfiring will reduce performance and thus could leave me doing 0 -100 in 30 seconds.
Coils on the LS are individual coils on each spark plug, known as COP's
Coils Over Plug. it's the part that provides the ignition to the spark plugs.
They need to be replaced, all 8 of them, including the boots that seat them and the spark plugs themself.
this shoulds restore full power of the engines capabilities.
When I go to replace this, I have to remove the covers to get to the
Coils and plugs, Should I find oil in the spark plug wells, I then have a
different problem of replacing the valve cover gaskets.
leaking oil gets to the Coils and shorts them out sort of speak.
my CATs could be getting plugged, this will also reduce performance.
If you are only getting to 100Mph in 30 seconds, your LS is lacking power
and something needs to be addressed.
If you don't know when the Coils and Plugs were replaced last, its probably
a good bet to start thinking about a little TLC tune up.
Folks here will be more then please to assist you in getting up to speed.
~ let us know how you make out.
ps: also be sure to replace air intake filter and run only 91 or better octane fuel in the LS.
