2002 Chevy Impala hesitation

2002 CHEVROLET IMPALA

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2 POSTS

Engine Performance problem
2002 Chevy Impala 6 cyl Front Wheel Drive Automatic 104k miles

I just had my trans serviced & oil changed and a couple days later my car hesitates upon acceleration when warm especially @ low speeds. I doubt its anything to do w/ trans but worried it may be timing belt? i've looked online and found lots of scenarios just wandering what the most likely cause may be considering my make/model/mileage/year etc.

Apr 20, 2009 at 3:27 PM

RASMATAZ

✓Experienced Mechanic
75,988 POSTS

2002 Chevy Impala hesitation

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

Apr 20, 2009 at 3:57 PM

RASMATAZ

✓Experienced Mechanic
75,988 POSTS

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

Apr 20, 2009 at 4:23 PM

LCGATOR