2001 Mercury Cougar drivability problems

2001 MERCURY COUGAR
87,000 MILES • 6 CYL • FWD • AUTOMATIC
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01COUGMAN
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I have a 2001 Mercury Cougar with 87k miles. It has an automatic transmission and 2.5 liter Duratec. Recently the car started backfiring & bucking when going up hills and also when the accelerator is applied hard. I am also experiencing unusual RPMs and my interior lights will subtly flash. I realize that the latter is a separate occurance from the former. The work that has recently been performed includes: new 02 sensors, MAF sensor, Solenoid sensor as well as spark plugs and wires. I'm beginning to believe that my mechanic is playing the lotto instead of diagnosing the problem.
Mar 17, 2011 at 4:42 PM
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RASMATAZ
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Could be caused by one of the following below

Oxygen sensor.
Catalytic converter.
Fuel injectors dirty/sticking.
Mass airflow sensor/Airflow meter.
Throttle position sensor.
Crankshaft position sensor
Knock sensor
Manifold absolute pressure sensor.
EGR Valve
Fuel pressure regulator leaking or defective fuel pump.
Fuel contamination.
Foul/defective spark plugs.
Open spark plug wires.
Ignition coil/Coil packs defective.
Incorrect ignition timing.
Cap and rotor.

Note:If it doesn't apply disregard it and keep testing.
Mar 17, 2011 at 7:28 PM