Took out old wall oven was left with 5 wires red ,black, white ,yellow and green bought new oven 4 wires black ,white , red and green what to do with yellow and what connected reds and black and whites and green to ground wire. When thing lights up , fans on but oven not heating up , *** help.

You need to trace back and see where that yellow goes. This is not at all typical in the US pr Canada.

If you provide the make and model number of the old oven, perhaps the diagram can be found to determine what the yellow connected to in the oven.

Is there a diagram on or in the oven? There usually is one someplace.

took out old wall oven was left with 5 wires red ,black, white ,yellow and green..........
Maybe I am confused. Is the yellow wire in the wall?

It could be, and I assume it is, but I also assume it was connected to something on the old oven.