blower problems

I have a goodman electric furnace, the blower works on summer fan but when a call for heat the blower barley turns. the heat strips come on and it shut off on high limit. it's a new capacitor.

 

You have a motor with winding connections for at least 2 speeds. Usually a higher speed for cooling and a lower speed for heating. If it starts and runs fine on cooling speed, the capacitor is good. My opinion is the motor's run winding has a defect and the motor needs to be replaced. In the meantime you could still use the furnace for heat, but at the higher speed. You would need to remove the signal from the relay causing the motor to run at slow speed to the relay causing the motor to run at high speed. I would need to see the schematic and ladder diagram for the furnace to be more specific.

 

I did change to a different speed and it did the same thing, it acts in heat mode like a bad capacitor but i know it isn't that. the fan relay board was changed also. its a goodman mbr 1600

 

Welcome to the forums.

You didn't leave the exact model number so I can't tell if it has a two or three speed motor.
You didn't leave the heat kit model so I'm not sure which sequencer is used.

If it is only a two speed motor...... there is only one operating speed for heat and A/C.
If it's a three speed motor.... there are two speeds used. A/C is controlled off the timer board
Heat is controlled from the sequencer in the heat section.

There should be a wiring diagram on the back of the service door that will have blower details on it.