Engine light on and wont go off and blows white smoke on 2006 Jeep Grand Cherokee

My jeep blows white smoke out of the tail pipe when i start it but stops after a few minutes. The engine check light is on and keeps coming after being cleared 3 times by a shop. 2 times by a shop once by a dealer. The code says that it has a misfire on the 8th cylinder but it has only misfired one time, all though it was shaking like crazy when it did it. It also lost all of its coolant once but hasnt lost any since. I had the spark plugs replaced to fix the misfire and seemed to but the computer doesnt seem to think so. Unfortunatly i havnt been driving it as much as i used to because to protect it from people at work, (no respect for nice looking vehicles), i dont know if that has any effect or not but im clueless and dont want to blow thousands of dollars at a dealer to find out that its not what i paid for. Thanks for help

by in Maryville, MO on November 08, 2012
4 answers 3 comments
ANSWER by on November 08, 2012
HAVE A COMBUSTION LEAK TEST PERFORMED AT MOST ANY REPAIR SHOP. BEST GUESS IS HEAD GASKET LEAKING COOLANT INTO COMBUSTION CHAMBER. THIS TEST IS FOR COMBUSTION (Co) IN COOLANT SYSTEM AND IS VERY RELIABLE.
COMMENT by on December 17, 2012
sounds like head gasket, probably reseals when warm. I have used a sealant with great sucess try Bars Leak
ANSWER by on November 08, 2012
blown head gasket
COMMENT by on December 16, 2012
Thats what i was afraid of, any one know how much a head gasket job will cost
ANSWER by on November 09, 2012
get a diag from your mech could be haed gaskets
ANSWER by on November 15, 2012
sounds like head gasket try a manufacturers sealant
COMMENT by on December 16, 2012
Yes, the head gasket tried the manufacturers sealant...and failed!