1999 Mitsubishi Eclipse Surging and Sputtering

1999 MITSUBISHI ECLIPSE
169,000 MILES • 4 CYL • 2WD • AUTOMATIC
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PHOENIXUMF
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I bought my Eclipse at a salvage yard a year ago and recently finished completely rebuilding her. Recently, however, at VERY low speeds(in parking lots, etc.) her acceleration has been surging. It felt like I was pumping the accelerator even though my foot was steady. She also has a rough idle at stop lights, which seems like maybe her EGR valve or a vacuum leak. Today, however, at the drive-thru, she started sputtering and misfiring, her RPM's dropped down to 4 or 500. We left, and at the next stop light she did the same thing, but died completely. I tried to start her back up twice, successful the second time and drove her home. Any ideas?
Jun 8, 2009 at 5:35 PM
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RASMATAZ
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Possible Causes:

Dirty fuel injectors (cleaning the injectors often fixes this).
Bad MAP (manifold absolute pressure) sensor
Bad TPS (throttle position) sensor
Bad or dirty MAF (mass airflow) sensor
Low fuel pressure (leaky fuel pressure regulator or weak fuel pump)
Vacuum leaks (intake manifold, vacuum hoses, throttle body, EGR valve)
Bad gasoline (fuel contaminated with water or too much alcohol)

Sometimes, what feels like a hesitation is actually ignition misfire rather than lean misfire. The causes of ignition misfire may include:

Dirty or worn spark plugs
Bad plug wires
Weak ignition coil
Wet plug wires
Jun 8, 2009 at 5:55 PM
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PHOENIXUMF
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Wow. That's a long list. Is there any additional information I could provide you with to whittle that list down?
Jun 9, 2009 at 10:02 PM
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RASMATAZ
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Check the fuel pressure with a fuel pressure gauge and comeback with the pressure readings.
Jun 10, 2009 at 1:48 AM