1993 dodge 4x4 p/u 3.9L

1993 DODGE RAM
156,000 MILES • 6 CYL • 4WD • AUTOMATIC
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PAL
  • MEMBER
  • 2 POSTS
Truck runs perfect...except when driving. Driving along normally when out of blue your giving it gas but it starts sputtering with medium backfire and if you let off gas truck will idle as you pull off road to stop. Then I turn it off wait 5 or so seconds start it back up and all is normal but reoccurs again within a mile. I have replaced fuel pump, cap, rotor, coil, throttle body incl. All 3 sensors on throttle body. Pulling my hair out need help.
Mar 15, 2011 at 11:02 PM
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RASMATAZ
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  • 75,992 POSTS
Do you have a check engine light on when its happening?

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 15, 2011 at 11:04 PM
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PAL
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The check engine light does not come on while this is occurring, before or after. But when I first start the truck in the morning there is a semi-quiet whistle that goes away as it warms up. Also I brought the truck from Minnesota to Colorado where its now at about 9900ft...Could the elevation be a factor? Drove great all the way to CO. Problem started after I got here.
Mar 15, 2011 at 11:16 PM
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