1989 gmc k1500 225,000 miles 5.7

1989 GMC C1500
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TMD14
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my truck has been idling poorly for the past few weeks, for example after the truck warms up it idles so slowly that it dies. the truck always starts back up right away. i replaced the idle control motor but that did not fix the problem. i performed a tune up (fuel filter, wires, plugs, rotor, cap) and after about 200 miles of smooth running the engine misfires and dies while driving although it still starts up right away. the engine sounds as if it is not firing on all cylinders.
Apr 9, 2007 at 4:10 PM
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FIVE STAR
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You may want to check all the ground wires to the engine. I recall having the same problem with another 350 in an older truck. There are a bunch of ground wires giong to the intake manifold around the thermostat housing. You may have a broken wire in that area or a corroded connection.
Also make sure you have good fuel pressure.
Good Luck
Apr 14, 2007 at 8:34 AM
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