Ok my car missfires at idle and at about 20 mph, Ive replaced plugs, wires, cap, rotor, fuel filter, air filter but not the coil though, and Ive been getting a code 44 ocasionaly ( when the light comes on it only stays on for awhile then goes off and does not come on till days later) , the O2 sensor has been replaced about 3 months ago could this been an intake leak? Any ideas would be greatly apriciated, Im getting terrible gas millage right now the way it is thats why Ive been leaning twards the intake gasket leaking.

 

Intake leak, low fuel pressure, clogging injectors, MAP sensor errors, lots of possibilities. How do the spark plugs appear?

 

Not sure I need to pull one and check, but I think its the intake gasket leaking, it was leaking coolant once before and I poored stop leak in and that went away but leaks a little still, so im thinking its leaking in air as well, causing it to run lean and then the computer compensates by opening the injectors longer sucking up my gas.