my spedometer jumps all over when the car gets warm and it is over 70 degrees outside. Like today when I started out this morning the check engine light had gone off when I started the car, and the spedometer did not jump around at all, but as the car was getting warmer I drove for about 15 mile and the spedometer started flopping around and I drove another 10 to get home. and no check engine. My husband is in Iraq, and I really cannot afford a new transmission. Please help, is there a less expensive fix to this, my car runs and sounds great otherwise.