Mitsubishi Repair: car problem, worn piston rings, valve seals


Question
1992 eagle talon  manual mitsubishi 2.0 4 cyldiner
2 door when i start my enigine for the first time each day the idle is fine for about 2 minutes then my engine starts to idle up and down while driving and if i am stoped. i also have a weird smoke coming out of the muffler like a almost blue smoke i had some tell me it is common on these four cyclinder engines to have problems with the value guildes beacuse of the rubber pieces please help me thankyou  

Answer
Josh,
When the idle bounces up and down, that is a symptom commonly referred to as "Idle Surge".  It usually happens because the ISC (idle speed controller) is malfunctioning.  The ISC's job is to keep the idle speed set to around 750 PRMs when the engine is warmed out and you're not stepping on the gas.  If the ISC if bad, it'll continuously keep "guessing" as to what the correct idle speed should be.  So, the rpms will bounce up and down.  It's also a good idea to check the car's computer to see if there are any problems.  Read this article for further information:
http://www.90gsx.com/eclipse/cap/caps.htm

If the ECU is malfunctioning, it can also causes this problem.

Blue smoke coming out the exhaust is usually caused by leaky valve guides, valve seals, or worn piston rings.  This can happen on any older car; 4-cylinders or more.  As long as you're consuming less than 1 quart of oil per 1000 miles, the leak isn't too serious.  If it's more than that, you may want to consider having a cylinder head rebuild if you plan on keeping the car for a considerable amount of time.
Good luck!