It could be a # of things; Piston rings,Valve seals,Oil returns stoped up, Leaking
intake manifold, Over filled with oil. To much fuel,engine running rich.
What color is the smoke ?? What year and engine size, This would help me answer
The question.
heatercore
change your ECT sensor. It tells your vehicle if it is too hot to operate.
Check for a blown fuse.
Several problems can cause a 1999 Blazer not to start. There could be a fuel problem or a firing problem. Check for fuel pressure and ignition spark first.
The transmission for the 1996 Chevy 3500 could be jumping from overdrive for several reasons. The transmission could have a vacuum or electrical problem causing it to come out of overdrive. Or, there could be an internal valve problem causing this to happen.
The check gauge light on a 2000 Chevy blazer could be several things. The oil could be low or the other fluids may be low. Take notice of all the gauges. One or more may be out of its normal parameter notifying you there is a problem.
The 1998 Blazer could have several problems causing rough idle. Check the air filter, fuel pressure, and EGR valve for a clog to look for the problem.
Water in fuel system, bad wires , distributor cap, spark plugs, theres a lot of things that could cause this problem, Is your check engine light on, If so you need to have the engine scaned to see what the code is and then go from there. Hope this helps.
One can buy Chevy Blazer part son Houston when one goes to the site Chevy+in+Houston. This site offers used Chevy as well as Chevy Blazer parts. Or one could go online to sites like Auto Trader.
There are many places where one could find maintenance tips for a 200 Chevy Blazer. One could check websites such as Fixya for information regarding maintenance on this vehicle.
Could be the driveshaft.
I had a similar problem with my 95 Blazer. The problem I had was with the spider unit or the fuel injection unit. This went bad on me along with the fuel lines going to it. While I was driveing one day it just died. If you have gas in the oil this could be your problem.