Stop being led by snake oil industry product (7)
I believe the answer is:
asphalt
'oil industry product' is the definition.
'stop being led by snake' is the wordplay.
'stop' becomes 'halt' ('halt' can be a synonym of 'stop').
'being led by' means one lot of letters go next to another.
'snake' becomes 'asp' (asp is a kind of snake).
'halt' put after 'asp' is 'ASPHALT'.
(Other definitions for asphalt that I've seen before include "Pitch surface" , "surface of path" , "Bituminous road dressing" , "Road-surfacing material" , "Mixture of tar and gravel used in road surfaces" .)