4.3l gm motor- blue smoke/intake gasket/head gasket

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- Stagger Lee
  
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posted
9 years ago

Sun, Jun 8, 2014 10:17 PM

I recently bought a 95 GMC Jimmy 4.3Lwith 230,00 on it. Idle was rough so I replaced EGR, PCV, and IAC. Still runs rough but not as bad. Smokes pretty blue even when warmed up. SES light is on and now flashes. Last time it was driven the entire back of the truck was coated with oil. The Radiator isn't bubbling nor do I see any leaks of coolant or oil. Valve guides, bad intake manifold gasket, head gasket?????? Paid $1,000 bucks body and interior in awesome shape ,hope I didn't get hurt to bad???

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- clare
  
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posted
9 years ago

Mon, Jun 9, 2014 1:39 AM

I'd be betting on stuck, broken, or worn rings. Have you done a compression test and/or leak-down test?? Have you done a cyl balance test to know which cyl isn't pulling it's own weight?

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- bilz2765
  
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posted
9 years ago

Mon, Jun 9, 2014 6:48 PM

that oil could be from the tranny.

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- clare
  
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posted
9 years ago

Mon, Jun 9, 2014 8:20 PM

If it is, by now the truck would have stopped driving. Easy enough to check. Pull the hose from the modulator valve. It should be bone dry. Only problem is, this beasty is a 1995, which to the best of my knowledge uses a 4L60E tranny which doesn't USE a vacuum modulator.

Think the OP is safe to ASS U ME it is not transmission oil causing the smoke this time.

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- bilz2765
  
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posted
9 years ago

Tue, Jun 10, 2014 7:34 PM

My reply had to do with 'entire' back covered in oil. I had a 96 Blazer 4.3 and tranny cooked covering entire back. Think tail pipe would only cover half. My2cents.

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- clare
  
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posted
9 years ago

Tue, Jun 10, 2014 8:21 PM

SES light flashing and rough running along with blue smoke from the exhaust definitely points to engine, but yes, I did experience the back of my TRAILER being covered with oil when the torque converter seal on my Aerostar let go just east of Imlay City Michigan on my way to BC. I can guarantee if that had happened he'd know. The truck was virtually out of transmission oil in about a mile.