2006 Chrysler 300,
5.7L Hemi. The code
said random misfire in
cylinder one, put two
new plugs and a new
coil pack and a crank
position sensor and
it still idles rough and
the check engine light
came back on after
resetting it. Just so you
know I have 10 TVs in
this car in a massive
stereo system and possibly
have tapped into
some positive wires for
power and don’t know
if I have tapped into the
ignition wiring harness
or not. Fuel pump is
working and the fuel filter and fuel pressure
regulator seem to be OK. Not sure if it’s the
injector or if the fuel rail has proper pressure
but have been having wiring issues
and not sure if that has caused a problem
with the computer or PCM
It could just as easily be a real mechanical
problem: A burnt valve, bad cam, lifter,
MDS solenoid, leaky injector, piston ring
or ring land, head gasket, cracked head,
etc. Some of this would show up on compression,
leakdown, or cooling system
pressure test, I had one that would misfire
when cold only, it would smooth right out
when hot. I stuck a borescope into the
cold cylinder, I could see drops of coolant
on the piston top. A new head gasket
fixed it.
