Q: Driving down the road oil pressure red light comes on no check engine comes on but car starts to sound like a diesel truck

The oil pressure warning light will come on if oil pressure falls below a safe threshold. It is possible for there to be plenty of oil in the engine but, due to a fault in the oil pump, oil pressure falls too low. Oil pressure can be tested using an external gauge, connected to an access port on the engine block, but if pressure is truly low obviously running the engine even during the test contributes to the damage. If you do use an external gauge, just make the test as brief as possible. If oil pressure is low, it is possible to install a new oil pump if the pump is defective but of course there is the possibility that the engine has already incurred some damage. The recommended service to request is an oil pressure inspection/diagnostic and the responding certified mechanic will let you know why the light is on and what the required repairs will be. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.