Help with older Napa R/C car

[Bobbyocean]

I recently dug out my old #15 Monte Carlo Napa Racing electric car. It runs off the 9.6V battery pack and has a three speed transmission. I've had it about ten years and stopped running it because it only wants to go in reverse sometimes, and forward once in a blue moon. It turns just fine... I have no idea what servo or anything is in it. I took it all apart and cleaned it up but that didn't seem to make a difference. I'm guessing broken wire but I traced them all down and can't seem to find any loose or broken wires.. Could the old 9.6V battery be making it act like this??? If anyone can point me in the right direction on what to look for next I appreciate it. Thanks, Bobby.

UPDATE: So after playing around with it some more I think its the transmitter. I can shake it and the car will go in reverse just fine. But still won't go forward no matter what I do... Am I on the right track with replacing the 49MHz transmitter? Thanks again.