1993 GMC Sierra

J.BUCKLEY21

MEMBER
1993 GMC SIERRA

Engine Performance problem
1993 GMC Sierra 6 cyl Two Wheel Drive Automatic +80000 miles

Hello, I own a 93 GMC sierra 1500 2 wheel 4.3 liter. I lost power on take off until I hit around 15 - 25 mph then it picks up on acceleration and it sounds like it does not shift right sounds rough. So I have changed the following things on it to try to resolve but I am stumped, I changed air filter, gas filter, PCV gaskets, checked the cad converter for clogging, checked transmission fluid but looks good good color and density, cleand carbirator out, and check oil it was dowqn approx 1/2 quart filled it but still no change.

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

Lack of acceleration, chugging, hesitating, bogging, misfiring etc. Could be caused by one of the following below:

Start here inspect and test all the items below and comeback with some results.

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.
False air leakage.
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.