Engine component to inspire commercial perhaps? (5,4)
I believe the answer is:
spark plug
'engine component' is the definition.
(component in a car engine)
'inspire commercial perhaps?' is the wordplay.
'inspire' becomes 'spark' (I can't justify this - if you can you should give a lot more credence to this answer).
'commercial perhaps?' becomes 'plug' (plug can mean an advertisement or promotional item).
'spark'+'plug'='SPARK-PLUG'
'to' is the link.
Can you help me to learn more?
(Other definitions for spark plug that I've seen before include "starter" , "Device screwed into a cylinder head" , "Ignition device in an internal-combustion engine" , "Electrical device fitted in the cylinder heads of an internal-combustion engine" , "Does it help to start driving" .)