When driving my car for an long period of time the CHECK ENGINE light will come on. The car will continue running fine while constant throttle is given. as soon as it sits in idle the RPM's begin to drop and the lights begin to dim until it shuts off. Most of the time the car will start right back up.
Also when starting the car all the electircal goes out i pull the key out and try it again and it will start up.
where should i start looking for a problem?