Thanks for help. I do wish I could locate a service manual but have had no luck. I have replaced the accel control box with a supposed working unit. It didn't change anything. Here's what I did find. There is a set of dual contactors connected to capacitor. It does not always engage. But when it does truck takes off and seems to operate properly with the accelerator pedal pressed either partially of fully. Then it seems like it dies out after a few seconds. Have no idea hat should activate that set of contactors. Thanks again for any and all help