Hyundai Coupe 1997. Cuts out when driving over bumps but only in the mornings.
There is no option for Hyundai Coupe 1997 in the selection box so please ignore selected car. So i leave for work at 6:30am and once im driving over bumpy roads the speedometer starts to flicker up and down causing the car to jolt. while doing this the check engine light and seat belt light illuminate just as though starting the car. Sometimes the car will be ok and it'll stop but other times the car completely dies. Upon trying to restart the car i get no lights on the dash at all and the car wont restart. After waiting a while the car will restart again. I took a video of the car acting up (On a private road near work) and showed it to an auto electrician. The auto electrician couldn't get the car to act up as they didn't open until later and it seems to never happen when its warm. They had it plugged in to 2 diagnostic machines with no error codes displaying. Could the car be getting moisture to some electrics somewhere or could this be something else? Thanks in advance.