Thank you for responding. Yes it is Towmotor Mitsubishi made by cat. No one has had a laptop to attach. It has a light that flashes a code but its related to a temp sensor being removed before I got it. My son tested the accelerator sensor and it test good. I'm guess that's what you refer to as rpm sensor? He tested when it was running correct and in limp mode both way's tested correct. I believe I can get a mixer but the throttle body is discontinued when I spoke with Cat this am. They do have the accelerator sensor but it is expensive so I'm trying to figure it out for sure before ordering more parts. I hope it's not the ECU, it's really expensive. This has been going on for months now and I have a large shipment coming the end of the week.