1982 GMC S15 carburetor

1982 GMC S15
114,000 MILES • 4 CYL • 2WD • MANUAL
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BRUCE MORGAN
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i have an 82 s15 1.9l and sometimes it runs rough and backfires... i noticed that the exhaust pipe from the manifold gets red hot (cut out cat and muffler thinking one may be clogged) it used to only do it when it was cold and if i kicked the gas peddel and shut off the truck it would go away...now it does it all the time.... i shot carb cleaner through it and on it looking for vac leaks but didn't find any...
Feb 21, 2009 at 11:56 AM
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JDL
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How long since a tune-up? Does the carb choke work like it should? How about timing?
Feb 21, 2009 at 12:08 PM
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BRUCE MORGAN
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new plugs wires cap rotor timing at 6 deg btdc all thiat checks out it seems like it's something in the carburetor. it would go into high idle and come out when i kicked it down but it started this running rough backfiring and missing but if i either turned it off or kept kicking the gas it would finally stop...well thats not working now....
Feb 21, 2009 at 1:54 PM
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JDL
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If you think it is the carb, maybe it needs a carb kit? The backfiring makes me wonder about a valve issue?
Feb 21, 2009 at 2:50 PM
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BRUCE MORGAN
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sohc? i don't know much about these motors...would a sticking valve make the exh pipe red hot? i mean litterally glowing red... if valve was sticking i wouldn't hear it on an ohc motor right?
Feb 21, 2009 at 5:46 PM
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JDL
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Hi, right now I think the fuel mixture is too rich. I can't access a lot of info on your year and model.
Feb 22, 2009 at 11:03 AM