Actuation problems with my motor controller.

Projects General Guidance
9 
void loop() 
{ 
  int value;
  for(value = 0 ; value <= 255; value+=5) 
  { 
    digitalWrite(M1,HIGH);   
    digitalWrite(M2,HIGH);       
    analogWrite(E1, value);   //PWM Speed Control
    analogWrite(E2, value);   //PWM Speed Control
    delay(30); 
  }  
}

If you are using the code sample from the link it is not appropriate for a solonoid valve.
Crazylgels suggestion is OK.
OR
Use a power N-MOSFET.