94 GMC Sierra stumbling

1994 GMC SIERRA
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A-TRAIN
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1994 GMC Sierra 4.3L V6 200,000 miles
I have been experiencing an intermitent hesitation or stumble in my truck. In park idle seems fine. When cold runs fine. When warm, problem occurs sometimes, and beginning to happen more often. Happens stopped in drive gear, or when at constant speed, but most often and noticable when accelerating. Replaced plugs, wires, fuel filter, O2 sensor, PCV valve, EGR solenoid and valve recently. Distributor, rotor, and fuel pump 40k old. Also, the air filter was covered in gas. Checked timing: at 8 degrees BTD ECM plugged in with +/- 2 degree "wobble" at idle.
Feb 25, 2007 at 6:23 PM
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CHEVY22
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is the enginelight on??

jim
Feb 25, 2007 at 6:26 PM
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intermittently, but when it was i got a code 32, which is why i replaced the EGR valve and solenoid. Haven't drove it long enough to see if comes back on again.
Feb 25, 2007 at 7:31 PM
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CHEVY22
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you should be ok unless there is a carbob buildup in the intake

jim

oh and leave some feedback if you were happy with your help , we all donate our time here helping others free of charge
Feb 25, 2007 at 7:45 PM
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So, the carbon build up might explain why i'm still getting the hesitation/stumble? I used a paperclip to clean out the EGR passage as suggested in answer to another question. Next step, remove, clean, and replace gasket for intake manifold?
Feb 25, 2007 at 7:57 PM
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CHEVY22
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at least check the passaged , the intake can really get gummed up inside so bad that i have just replaced them before ,

let me know

jim
Feb 25, 2007 at 8:19 PM
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found that i was leaking antifreeze from intake. Replaced the intake manifold gasket this weekend, and the stumbling is gone. check enginge light doesn't come on either, but i don't know if that was from replacing the EGR solenoid and valve or the gasket.
Mar 12, 2007 at 6:39 PM
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CHEVY22
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could have been a combination of both , glad it worked out

Jim
Mar 12, 2007 at 6:45 PM