You probably have a burned light bulb, either in the front or rear.
The trun signal lever needs to be replaced.
This may very well be a problem with your ground connections at that turn signal.
It's telling you that you have a problem. Get a code scanner and find out what the problem is. that's a misfire .i had tht problem and i changed the spk plug cable
Faulty Turn Signal flasher Faulty Turn Signal Switch
your rear bulb is blown - replace the bulb The turn signal blinks fast because the bulb is going out. That is also why the others dont blink.
turn signal relay is bad
Most likely, one of the right side turn signal bulbs is burned out.
Buy a "highway" turn signal flasher
Flasher relay.
The reason is because you have two flashers. One works with the hazard light circuit and the other works with the turning sigal circuit. Replace the flasher and if that does not work you should check for a steering column problem or a switch problem. Good Luck
Why would you want the blinker faster. They should blink at factory specs.
Check your bulbs and your flasher.