92 GMC Sierra c1500 blowing white smoke

Discussion in 'GMC Truck Forum' started by chrismclaws, Apr 10, 2011.

  1. chrismclaws

    chrismclaws Member

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    When ever the truck is sitting and has cools down when I start it there is a puff of white smoke that comes out of the tail pipe. It's a 1992 Sierra c1500 GMC with 169,000 miles on it. Is this puff of smoke burning oil or to much gas? I do have to put in about a qt of oil by the time I have a oil change evey 3 months.
     
  2. c15004ever

    c15004ever Senior Member

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    im no expert, but it sounds like your valve seals are no good. Common in these trucks around that many miles, my iroc-z does the same thing. Maybe someone else can explain it better
     
  3. turfking

    turfking New Member

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    My '93 has 134,000 miles with a 4.3L and it does the same thing.Valve stem seals are gone. I just watch the oil level and try not to start it in front of a crowd.
     
  4. gmctrucks

    gmctrucks Full Member

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    The seals can be replaced without taking off the heads talk to some local tech.
     
  5. jimboflies

    jimboflies Full Member

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    In my experiance , white smoke usualy means water vapor?
     
  6. darisb

    darisb Senior Member

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    My 92 K1500 was doing the same thing. White smoke at startup and it went away after it warmed up. My got progressively worse over sevearl months until it was blowing white smoke almost all of the time. The truck is an extra vehicle that I only drive once in a while. Keep any eye on your coolant overflow tank. The level should remain failr constant. If not, you've got a leak.

    I tried replacing the head gaskets, but it continued to blow white smoke. I pulled them a second time and took them to a local shop. The diagnosis was a cracked head. They sold me a rebuilts set for a very fair price. The owner gave me a long list of things to do when putting it back together. It's been running great ever since.
     

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