I have a 2001 Lincoln LS I just recently put Motorcraft spark plugs in my engine two weeks ago, but before I put new spark plugs in it was idling rough, lack of power, trouble accelerating wouldn't go past 50 miles per hour, bad fuel economy, also jerks when I put my car in reverse not the engine jerking but the whole car itself, and it's doing all of this still after new spark plugs have been put in I did not change the coil packs I can say that..... toke it to AutoZone last week & they read the check engine codes as cylinder 3 misfire and EGR valve failure...... also my car when it's in park or i say idling it has a very bad shake to it. Also when I put it in reverse it sounds like something's knocking in the engine but when I put it in Drive and drive the car runs normal afterwards. But that's all that's wrong with my car I believe so so if you can get back with me with your best answer I would appreciate it thank you very much.
My car has 147523 miles.
My car has an automatic transmission.
This may be a sign of a dirty or faulty mass air flow sensor. The mass air flow sensor is a unit in the intake system that monitors air intake as it is mixed with fuel prior to being injected into the motor. When this fails, it can cause an imbalanced air/fuel load to be supplied to the motor, which often results in the engine starving for air or fuel or, in some cases, over-fueling the motor. Over-fueling results in excess fuel being un-burnt and also creates a loss of power and poor fuel mileage.
This is what causes the hesitation or loss of power you describe, and can also cause the engine to struggle to idle for the same reason, and may also create a misfire due to lack of fuel (in some cases).
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