hey do you guys know what is code 43 on a 1991 accord how to diagnose it?

 

yes, you threw a fuel supply code... the most common cause of this is a faulty fuel pump or filter... Find your fuel filter. follow the line coming off of your fuel rail to the passenger side firewall... the short black cylindrical thing that it's connected to... this is your fuel filter... Have a friend crank the car over while you loosen the supply line a little bit... The supply line is the line NOT going to your fuel rail, it comes out of the firewall into the fuel filter... A constant flow of fuel should be coming out of the fitting that you loosen...

If your car doesn't start, then I would replace the fuel pump... But if your car starts up and drives, then I would look into other things...