cooliant in resvoir tank will be brown
freeze plug has blown out or leaking
It would be a good thing to see where it is leaking from....
Blown fuse.
Have the high pressure valve checked.
Because the plastic housing is cracked. That is what happened to mine.
Most likely cause would be a blown fuse.
heater core is leaking.
Heater core leaking.
It could be three thing... 1. You blown a fuse 2. You have a faulty switch 3. Your Marquis need to be rewired
More than likely a blown fuse.
by disconnecting the coil or plug wire and the fuel injector connector also for that cylinder.
Intake manifold gaskets are leaking, intake manifold is warped.