Automotive electrical disturbances occur regularly in the vehicle primarily due to switching on and off of various vehicle components from the starter motor to electrical and electronic systems.
There are both emissions and immunity tests required by the standards, of which there are many. The main standards like ISO 7637-2 and ISO 16750-2 define both how these pulses must be simulated and how they are measured and with what limits. The vehicle manufacturers who are ultimately responsible often take these requirements and expand or modify them.
For immunity testing you need a transient generator (NSG 5500), some kind of coupling network, a battery simulator (PA 5840 or PA 5740) and a function generator (now integrated with NSG 5500).
For emissions testing the AES 5501 includes just about everything you need, switches, artificial network, even the oscilloscope probe.
Many OEM requirements include ESD testing similar to ISO 10605, for which an NSG 438 is highly recommended.