s/n 70473. 4.3 vortec V6 gasoline only with throttle body injection. When machine is cold (I would say sits over night in temps lower than about 40F) the throttle kicks out if you push it more than about 25% and turns the check engine light on. You can restart the machine and the throttle will come back but the engine light stays on. The problem becomes less persistent the warmer the machine gets. We use GCP display to pull codes and I got code 87: Fuel pressure lower than expected. I tired replacing the fuel filter but this did not solve the issue. Just curious if anyone has seen this before. Maybe has some more info on troubleshooting. I think it might be the fuel pump but I don't have a spec on what the output should be, the manual I have doesn't say much about the fuel system. I measured the fuel pressure during operation and its at about 64 PSI at idle. drops to around 55 at full throttle. When the light comes on it looks like the pressure drops to about 54.