Hyundai Repair: fail when reach the operation temp., hyundai elantra, operation temp

Question
A hyundai elantra 2000, motor 2.0 When start the motor and is cold it work normal, acelerate normal but when reach the operation temperature begin to fail when acelerated the motor and have no power to run, (only when motor warm), sound like a lawn mower, I think its like something electric open when hot, but have no idea. The gas filter and the pump were changed, cleaned the injector, and the spark plug cables was changed too, but continue with the same thing. I have a headache with this problem. If some body have an idea about this problem I thanks so much.

Answer
It sounds like you may have a misfire issue.  A carbon track on the ceramic of the spark plug will often cause a misfire only when hot.  If one of the plugs is carbon tracked, you should replace the plug and make sure you clean the carbon out of the boot on the plug wire.

Also, if you're misfiring, the check engine lamp will typically come on.  Is the check engine lamp on?  Does it flash when the problem occurs?