Question about 1999 GMC Jimmy

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Coolant levels are getting low without any visible signs of leaking on a gmc 4.3 liter. Father-in-law heard 4.3's are notorious for intake mainfold replacement....Any truth too this and is it a costly repair

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Look down between the upper and lower intake manifolds where you can see the injectors seated in their ports ---- you will need aflashlight--- if the intake gaskets are leaking you will see the colant around the base of the injectr at its ports. you can also see leaking colant at the ends of the motor assy in the area where the heads mount to the block. if the head gaskets are blown or leaky, the coolant can be getting sucked into the combustion chamber and blown out the tailpipe ---it will continue to expel water even after it has warmed up ---looks like condensation but it is coolant. 1200.00 to 1800.00 depending where you take it. my daughter had this problem and she spent 1200.00 of my money at a dealer to repair it. 2 weeks later I had to do the entire job over myself --- she had it done in florida and i did it over when she brought it back to chicago and it had the same problem plus all the **** the dealer left loose or left off. your problems are just starting ---- look to get rid of it before it isn't worth anything just like the malibu I bought new in 2002 when I was a GM employee. should have been a recall --- not to mention anti theft and a host of other problems

Posted on Jun 22, 2009


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