When I step on the gas the RPM does not go up but mph goes down go down and I loose power. If I just put alittle pressure on the peddle I can get some speed, but if I press too hard my speed goes down.

you mean acceleration sensor? there's no such thing to my knowledge, but there are sensors that monitor your speed, which is how your speedometer and tachometer work, also there are speed governors, but they do not affect how your motor performs. There's a throttle position sensor that could be faulty (that's the part that tells your cars computer how far you have the pedal down and how much fuel to deliver to the motor), if your engine has a carburetor then it may need adjustment or replacement. There are too many variables to diagnose your problem without having a good look at your system. I recommend taking your vehicle to a reputable mechanic to have it checked, but if they tell you it's your acceleration sensor they are trying to rip you off and you should go somewhere else. Also since you said there was no smoke you're not running rich (rich is when there is more fuel than there is oxygen to help it burn and so it doesn't burn completely). Perhaps you could be running lean which is the opposite of rich (not enough gas going through). you mean acceleration sensor? there's no such thing to my knowledge, but there are sensors that monitor your speed, which is how your speedometer and tachometer work, also there are speed governors, but they do not affect how your motor performs. There's a throttle position sensor that could be faulty (that's the part that tells your cars computer how far you have the pedal down and how much fuel to deliver to the motor), if your engine has a carburetor then it may need adjustment or replacement. There are too many variables to diagnose your problem without having a good look at your system. I recommend taking your vehicle to a reputable mechanic to have it checked, but if they tell you it's your acceleration sensor they are trying to rip you off and you should go somewhere else. Also since you said there was no smoke you're not running rich (rich is when there is more fuel than there is oxygen to help it burn and so it doesn't burn completely). Perhaps you could be running lean which is the opposite of rich (not enough gas going through).