My mitsubishi chariot 98 vibrates when idling, what could be the problem?

A few possibilities are worn engine mounts (the rubber mounts that take away engine movement and vibration).....or rough engine idle ( maybe poor compression in one or more cylinders or other factors)....or maybe the engine idle speed is too low (typically 700 to 1000 rpm is normal depending on if AC is running which takes up more rpm) Alex

You should get a tune up. Have the spark plugs changed. Have the spark plug wires changed, the cap and rotor. Check the timing. Also can be buildup on the injectors, Run some injector cleaner thru the system. Buy a high octane gas 91 octane. Get a bottle of heat to put in your gas, this takes all the water out of it. If none of this works change your fuel filter, air filter....hope this helps.....