Every warning light on dash is on. on 1996 Pontiac Grand Am

warning lights comes on car will not start.When lights goes out car starts every time. Sometime when driving the light will come on but car keeps running but when i shut it off it will no start. If light is on and I hit a bump in the road the lights goes out and the tach works.

Asked by for the 1996 Pontiac Grand Am
I'm assuming you're talking about the check engine light.
The check engine light indicates that the computer has detected a malfunction in the engine/emission control system and has diagnostic codes and data stored which would be essential in diagnosing the problem.
A technician with a scanner could access the diagnostic codes and data and then be able to give you a diagnosis.
If it's the other warning lights, there must be an electrical problem, the fact that hitting a bump affects the engine points to a bad electrical connection somewhere.
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