On a new one piece washer and dryer unit,the neutral is grounded to the frame,so where do i connect the green wire from my 4 wire power cord?

Download the owners manual for your appliance and look for the 4 wire installation method.

If you have a 4 wire receptacle it is illegal to change the receptacle to a grounded neutral 3 wire "nema 10-30" type receptacle. It is likely that the sign nearby was installed when the 3 wire cord was installed (I assume the sign is on the appliance).

Here is the code requirement, but first two code definitions, the "grounding conductor" is the green or bare wire. The "grounded circuit conductor" is the neutral wire which is normally white.

NEC 250.140 Frames of Ranges and Clothes Dryers. Frames of electric ranges, wall-mounted ovens, counter-mounted cooking units, clothes dryers, and outlet or junction boxes that are part of the circuit for these appliances shall be connected to the equipment grounding conductor in the manner specified by 250.134 or 250.138.

Exception: For existing branch-circuit installations only where an equipment grounding conductor is not present in the outlet or junction box, the frames of electric ranges, wall-mounted ovens, counter-mounted cooking units, clothes dryers, and outlet or junction boxes that are part of the circuit for these appliances shall be permitted to be connected to the grounded circuit conductor...

(additional restrictions apply to allowance, full details at http://freenec.com/T95.html )

Correct.

Do not remove neutral to frame ground.

You'll not be utilizing the (white) neutral wire inside the cord.

I am assuming you did not change replace or tamper with the existing wall receptacle.

If so, stop. You had best summon an electrician.

I am also assuming the cord inserts properly into the EXISTING wall receptacle.

Snip off the bare end on neutral and cap it off--on applianfe end of cord.

Connect other 3 wires properly.

Plz employ an electrician sir if there are any above mentioned changes.