when i start my car i lose my dash, interior,and headlights as well as my radio until i hit a bump also there are no fuses blown what could be the problem
a loose connection somewhere. Have you tried thumping the dash?
A poor connection somewhere, likely a ground wire.
Run the engine at idle. With a gloved hand, shake and move the wires in the engine compartment. When you move a wire which causes the engine to stumble, that will be the one to tighten, or replace (if it’s a battery cable).
Here’s one more vote for a loose electrical connection, most likely a ground wire.
You didn’t tell us the make and model of the car, but I am going to guess that it is a European brand. Am I correct?
I too suspect that there is a bad wire connection but I think it is a power connection rather than a ground problem. There may also be a power relay connection causing this problem. You may be able to track this problem down by using a screwdriver handle to tap on suspected areas while the trouble is occurring. I would start with the power panel under the hood and any connectors near there. Then move to the dash fuse panel and connectors under the dash if you don’t have any positive results under the hood.
If the trouble area dosen’t show up after looking into the areas mentioned then check the ignition switch area for the problem.